An examination of the role of collective efficacy and structural equivalence in the formation of vigilante groups in Mexico

Vol.:(0123456789) ORIGINAL PAPER

An examination of the role of collective efficacy

and structural equivalence in the formation of vigilante groups in Mexico

Adam Dulin¹

Received: 6 November 2020 / Accepted: 27 July 2021 / Published online: 1 September 2021

© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2021

Abstract

This article builds on the dearth of academic literature explaining the emergence of vigilante groups by incorporating two different theoretical perspectives: collec- tive efficacy and structural equivalence. Through the use of qualitative compara- tive analysis (QCA), this research sampled municipalities in the Mexican states of Guerrero and Michoacan and operationalized a set of conditions based on previous research and the aforementioned theoretical perspectives. The results of the QCA demonstrate that collective efficacy was associated with the most unique explanatory pathway and provided the greatest coverage of vigilante group formations. Equally important, the conditions operationalized in this analysis provided for a total of four explanatory pathways that explained each vigilante formation without any contradic- tory outcomes (non-formations).

Introduction

Understanding vigilantism is a critical issue due to its global scope and impact (Fel- bab-Brown 2015). Viewed as “non-state policing”, this phenomenon represents a community-driven alternative to perceived insecurity (Fourchard 2008, p. 17). Citi- zen perceptions of insecurity are, however, linked to questions of state sovereignty and who holds the monopoly on providing security. In fact, vigilantism "questions the very contours of the state" (Sundar 2010, p. 116). In many countries this phe- nomenon represents a national security concern due to the subjugation of state sov- ereignty and the perceived tendency for vigilantism to morph into more dangerous entities (Sundar 2010).

The views expressed in this article are those of the author, and do not necessarily reflect those of the U.S. Department of State or the U.S. Government.

* Adam Dulin

StdALD15@gmail.com

1 US Department of State, Washington, DC, USA

The presence of vigilantism changes local and regional security dynamics and has a far-reaching impact through the autonomous use of threats and violence (John- ston 1996). Indeed, the means by which these groups conduct business are as varied as the contexts in which they are form. Vigilante groups take a variety of forms and target a variety of perceived problems in their respective societies. And the phe- nomenon carries both positive and negative connotations, evoking the human desire for security and the desire to go outside the boundaries of the law, if necessary, to achieve it (Sundar 2010).

Despite its importance and prevalence, the factors that drive vigilante formation are understudied. Much of the academic narrative on their formation is anecdotal and centers on filling security gaps due to state ineffectiveness (Phillips 2017). Yet

“it is insufficient to point at the “absence” of the state or its incapacity to provide for justice” in explaining this phenomenon (Kloos 2014, p. 62). Further, this focus on the state fails to account for the other side of the vigilante equation—the community in which it forms. Lastly, few studies of vigilantism have explicitly focused on the formation of groups, confusing vigilante formations and vigilante acts.

This study aims to better understand the conditions under which vigilante group forms by bridging the gap between our anecdotal understanding and theory-driven mechanisms that aid in explaining this phenomenon. To accomplish this, the con- cepts of structural equivalence and collective efficacy are incorporated into the nar- rative on vigilante formations. The analytic approach relies on qualitative compara- tive analysis (QCA) to assess the impact of these perspectives while accounting for other explanatory conditions derived from the literature.

The analysis will focus on Mexico, where vigilantism is widespread and has proliferated in recent years (Phillips 2017). Mexican vigilantism has reportedly increased in the last decade owing to the increase in drug-fueled violence and the militarization of the state’s response to DTOs (Phillips 2017). The following section provides an overview of vigilantism in Mexico.

Mexico vigilante groups

The current wave of Mexican vigilantism (referred to as self-defense groups in many areas) has its roots in Guerrero’s Costa Chica region where, in 1996, dozens of communities from five different municipalities formed their own patrols to further reinforce law enforcement efforts in the region. This initial grouping was hundreds strong and its modus operandi in the beginning was to detain criminal suspects and hand them over to the state. However, within a few years they began to pass their own sentences on alleged offenders. This phase of self-help vigilantism in Mexico fell under the auspices Community System for Security, Justice Administration and Reeducation (referred to by the Spanish acronym CRAC), but they refer to them- selves as community police (Johnson 2007). By 2013, roughly 2000 people were involved in Guerrero’s self-help community policing efforts (“Se” 2013).

The CRAC have a legal basis in their formation and those who join their ranks are selected through an inclusive process. Until 2009, the community police out- fits were by and large unarmed. However, as if foretelling of events to come, these

groups began to arm themselves before the much larger growth of vigilante groups (García Ramírez and Martínez 2014).

The community groups that fell under the CRAC umbrella are distinctive from the vigilante phenomenon that appeared in 2013. The new wave of vigilantism had its epicenter in Guerrero and Michoacan, where the country’s war on organized crime continues (International Crisis Group 2013). What sets Michoacan and Guer- rero apart from other earlier manifestations of vigilantism in Mexico is that these informal social control groups were propelled by years of victimization by DTOs (Salgado 2013). The region witnessed the proliferation in kind of drug traffick- ing organizations (DTOs) that fought for territory throughout both states, the state onslaught against DTOs, and the widening of the DTO criminal portfolios into tradi- tional organized criminal activity (Diaz and Perez 2015).

The first event occurred on January 5 in the Costa Chica region as a veritable uprising of citizens fed up with chronic insecurity (Phillips 2017; Espino 2016).

The residents of Ayutla de los Libres armed themselves on this day and established checkpoints around the town after a rancher who also served as police chief was kidnapped (Arista 2013). The state of Michoacan followed suit soon after when, on February 25, citizens in the municipalities of Buenavista and Tepalcatepec formed their own vigilante group. In Buenavista, the citizens were living under the extortive influence of the Knights Templar, who inserted themselves into the supply chain of profitable agricultural produce, especially lemons. This was referred to as the “tem- plar tax”. The number of vigilante groups proliferated soon after (Diaz and Perez 2015).

These new groups fell, for the most part, under the umbrella of the Unión de Pueblos y Organizaciones del Estado de Guerrero (UPOEG) (Cuevas 2014). In fact, it came as a bit of a surprise, during the first weeks of 2013, that the CRAC was not the group behind the vigilante activity occurring in various municipalities (Espino 2016). The UPOEG was an offshoot of the CRAC and was founded in 2012 after a public rupture between the two organizations (Comisión Nacional de Derechos Humanos 2013). Thus, in Guerrero or Michoacan, the vigilante question can be boiled down to two basic formations that citizens identify with—community police and self-defense groups (Diaz and Perez 2015).

Literature review

A number of academic studies examine factors related to vigilante group formation.

The vast majority of these studies are qualitative in nature and point to a number of different variables that explain the emergence of these groups. The most com- mon theme interwoven throughout previous studies is the role that insecurity plays in catalyzing vigilantism. While this may sound intuitive, it is quite nuanced in the context of vigilantism. For example, Gitlitz and Rojas (1983) found that cattle rus- tling was conducive to the formation of these groups in select Peruvian highland provinces. The authors place this criminal activity within the context of an exis- tential threat to peasant livelihood, as opposed to other forms of theft. This study of Peruvian vigilantism illustrates an important point about the insecurity that may

catalyze vigilante group formation—cattle rustling was a long-term acute problem that eventually became worse.

Nivette (2016) examined public support for lethal vigilantism in Latin America.

In formulating the factors that contribute to positive attitudes toward lethal vigilan- tism, the author relied on exposure to crime. The author’s findings support the role that exposure to violence can play in public support for lethal vigilantism (see also Adinkrah 2005). But how such exposure is perceived by the public, or constructed by political actors, implies a great deal of subjectivity. Thus, the punishment doesn’t always fit the crime in scenarios where citizens take vigilante actions; disproportion- ate responses may be taken for seemingly minor crimes (Godoy 2004).

In the Mexican context, Maus (2016) found that the type of control exercised by organized crime groups can play a role in vigilante group formations via varying levels of violence and extortion that create discontent among the local populace. A contagion effect has also been noted in which municipalities that have experienced vigilante group formations increase the odds that adjoining municipalities will form their own groups. This is due in part to the fact that crime and violence stemming from organized crime transcend administrative borders particularly as these criminal groups have regional ambitions.

Adding further nuance to the insecurity perspective, vigilante violence need not occur in response to criminal activity, at least in the strict legal sense. Vigilantism may address any “transgression of institutionalized norms” be they legal or cultural.

The social control activities aimed at enforcing communal conceptions of right and wrong is “nebulous” and requires an understanding of contextual factors (Johnston 1996, p. 229).

The extant literature also focuses on the inverse relationship between state power and citizen power. One of the earlier studies on this topic by Rosenbaum and Seder- berg (1974) posits a hypothesized positive relationship between vigilantism and the

“… belief that a regime is ineffective in dealing with challenges to the prevailing sociopolitical order” (p. 545). This particular conception falls in line with much later research that views vigilantism as self-help and informal policing, all linked to the absence of formal state control (Nivette 2016; Kucera and Mares 2015).

On a similar note, Abrahams (1998) placed their formation within the context of frontier zones, where the state fails to maintain control over illegitimate uses of vio- lence. Important in this conception of frontier zones is that they can arise both in the presence and absence of the state. In other words, they can occur in the face of state ineffectiveness. In such cases, in these frontier zones, vigilante groups are a “natu- ral” occurrence (Abrahams 1998, p. 52).

The emergence of vigilante groups to fill voids in state power has theoretical root- ing in pure sociology and Blacks (1983) assertion that formal and informal law are inversely related. This relationship has found some support in previous qualitative studies. For example, in an examination of vigilante groups in Mindanao, Austin (1988) found that barangay members readily contributed their time to semi-official and unofficial vigilante groups in their interest of community self-help. Thus, in the rural setting of the Philippines, less formal law was accompanied by more informal law applied by vigilante groups.

In an in-depth ethnographic account of vigilante activity in Cochabamba, Bolivia, Goldstein (2003) examined the discourse surrounding a particularly violent inci- dent in which residents in Villa Sebastian Pagador, on the margins of Cochabamba, imparted vigilante justice on suspected thieves. The author found in the context of Cochabamba that the absence of police is not necessary for the emergence of vigi- lantism, but rather the indifferent and ineffectual presence of police. In this sense, the author further contextualizes what it means to be on the periphery of state authority, as police are more inclined to respond in other urban areas where police action can be more effectively demanded by the citizenry. Thus, vigilante activ- ity seeks to “compel the state to live up to its own claims of legitimacy” (p. 24).

What is also evident in the discourse on Pagador’s vigilante activity is the cohesion and structural consistency of the neighborhood’s residents, a key characteristic that might help explain the ability of the residents to mobilize.

Adding to the nuance of vigilantism as community expression, Omach (2010) echoes the desire to express autonomy in the African context. Indeed, vigilante groups are historically rooted in Africa owing in large part to the “ambiguous nature of authority in peripheral areas” and cultural expectations on the role of community members in contributing to communal defense (p. 432). This cultural expectation parallels what has been termed a “tradition of lawlessness” (Gitlitz and Rojas 1983, p. 176).

In contrast to previous studies, Schuberth (2013) challenges the notion that weak states foment the formation of vigilante groups through their inability to provide cit- izen security. Rather, the author argues that vigilante group formation is an outcome of larger policy processes. As an example, the author cites criminal justice policy that, at its core, is aimed at preventing the spread of crime into economically privi- leged areas. These policies promote segregation and the need for poorly represented groups to fend for themselves.

Phillips (2017) conducted one of the few statistical analyses of vigilantism, with a focus on Mexico. The author posited that income inequality allows for both the structures conducive to the formation of vigilante groups as well as the requisite gaps in security that create the need for these groups. In other words, income ine- quality creates security inequality. Along with this implicit security gap created through wealth distribution is a labor force capable of organizing vigilante groups.

The results of Phillips’ analysis indicated a statistically signification relationship between income inequality and vigilante activity in Mexico.

Moving forward with different theoretical perspectives

The aforementioned studies inform the current endeavor with a number of fac- tors that must be considered when attempting to examine vigilante group forma- tions. Among these is the nebulous conceptualization of insecurity, be it insecurity in response to threats to a legal or cultural order and the various ways in which different crimes may create insecurity. Equally important is the absence (or effec- tive absence) of law enforcement and the inverse relationship between formal and

informal social control. Further, the absence of economic well-being may play a role through associated gaps in the provision of security.

While these factors are important, it is asserted that they fall short in comprehen- sively detailing the causal pathways that drive vigilante formation. In short, a theory- driven approach that allows for conjunctural causation is necessary. For example, despite the prevalence of the state weakness explanation for vigilantism, Schuberth (2013) asserts “general state weakness is not a universally applicable explanation for the emergence of vigilantism” (p.43). Further, Phillips’ (2017) concluded that

“vigilantism has diverse causes” in his statistical analysis of hypothesized linkages to wealth distribution (p. 1377).

Thus, two different theoretical perspectives are applied in this research. Both perspectives are complementary, examining the community features conducive to collective action. The first perspective, collective efficacy, addresses a community’s willingness to work together on social problems. The second perspective, structural equivalency, examines the structural features of a community as it relates to social homogeneity. The research objective is to determine if one or both of these theories aid in explaining the emergence of vigilante groups, while accounting for factors identified in the extant literature.

Collective efficacy

The basic argument of collective efficacy is straightforward: those neighborhoods with a sense of cohesion and a shared willingness to assist others will impact on the likelihood of neighbors engaging in informal social control measures. This per- spective derives from the social disorganization theory of crime. Within this theo- retical framework, community disorganization is “defined explicitly as the inability of community structure to realize the common values of its residents and to main- tain effective social controls” (Morenoff et al. 2001, p. 519). At the opposite end of the spectrum are those neighborhoods with high cohesion and “an active sense of engagement on the part of residents” (Morenoff et al. 2001, p. 521). The distinc- tion between collective efficacy and other conceptions of community cohesion is a shared belief in community capacity to actualize informal social control (Sampson 2002).

Within this theoretical perspective, however, there are those communities that have actualized this capacity, and those that simply feel they are up to the challenge.

Indeed, residents can report high levels of collective efficacy when there is little actual engagement in informal social control (Wickes 2010). Thus, there are limits to what a neighborhood can accomplish through informal measures; some are will- ing to tackle bigger problems, while some are not willing to do much at all.

The concept of updating is instructive as it pertains to differing levels of collec- tive efficacy. Updating acknowledges that collective efficacy relative to a particular task may depend on previous experience and the particular task in question (Hipp 2016). High levels of violent crime, for example, may impede a neighborhood with demonstrated collective efficacy on other tasks (e.g. minor crimes) from acting (Skogan 1989; Sampson et al. 1997).

In the current research context, vigilantism in many ways represents the pin- nacle of community actualization and thus an activity that many cohesive com- munities would be unwilling to engage in, despite their willingness to engage in other forms of informal social control. It is asserted here that collective efficacy must be a pre-existing physically “activated process” in order for it to catalyze vigilante formation (Wickes 2010, p. 436). Indeed, “communities that can effec- tively mobilize to regulate local crime can be understood to have high levels of collective efficacy” (Browning 2002, p. 834).

Structural equivalence

According to Mizruchi (1990) “Structurally equivalent actors are those with identical relations with other actors in the social structure” (p. 25). That is, two people in the same roles are related to other actors in different roles in the same way. It is expected that people of the same type (based on their position in a net- work) will act the same way toward other people in different network positions as they are “similarly socialized” (Burt 1978, p. 199). As an example, two teach- ers in two different school districts are expected to interact in similar ways with their respective administrations under this perspective.

Structural equivalence incorporates processes of imitation, or knowledge, of how others act. However, it also accounts for indirect processes positing that behavioral similarity does not necessarily equate to knowledge of others in a network. Relatedly, structural equivalence can also cause contagion amongst similarly situated people (Burt 1987). This contagion owes to “social pressure”

(p. 1327). If knowledge of other actors is present, this contagion can also occur as people in similar network positions (e.g. beholden to the same actors who are themselves structurally equivalent) use one another as reference systems in terms of “beliefs, attitudes, and behaviors…” (Fujimoto and Valente 2012, p.

1956).

This posited link between network position and behavior has untapped poten- tial in explaining the formation of vigilante groups. Equally important, this per- spective also explains attitudinal similarity through indirect processes whereby similarly situated actors perceive problems in the same way as they are subject to the same pressures. Thus, the intersection of similarly situated actors and crime may promote similarity in attitude and action that catalyzes vigilante group formation.

In keeping with the conjunctural foundation of this research, the following section discusses how the theoretical perspectives of interest were operational- ized in a manner that allows consideration of the different ways they may con- tribute to causal pathways. Indeed, the methodological approach combines criti- cal contextual issues in Mexico with the literature and the number of variables that may impact group formations. However, in the interest of parsimony, this research takes an approach to sampling that departs from previous research to allow for a deeper focus on contexts where inhabitants already feel insecure.

Methodology

Qualitative Comparative Analysis (QCA) was chosen under the assumption of equi- finality. In a nutshell, this implies that different explanatory pathways may lead to the outcome in question. In different pathways, explanatory conditions may play different roles depending on the other conditions present or absent in the pathway (Wagemann and Schneider 2010). Thus, this method is appropriate for the current research goal of assessing how different theories can help explain the phenomenon of vigilante group formation.

QCA is based on relations between conditions and outcomes and minimizing chaos through the dialogue between (and within) cases and the theory that guides the research. This approach allows the researcher to identify necessary and sufficient conditions for an outcome, in addition to the various combinations of conditions specific to an outcome (Ragin 1987). A specific type of QCA, know as crisp set, was employed in the current research. This QCA method involved dichotomization of conditions as explained in more detail later in this section.

The analysis entailed four phases. First was the selection of cases and develop- ment of thick case knowledge for each individual case. Following this, theoretical conditions were dichotomized, and a data table was constructed. In the next step, the

“QCA analytic moment”, a truth table¹ was constructed using the QCA package in the R software platform (Thiem and Duşa 2013). The truth table was then analyzed to identify and deconflict contradictions between sets of conditions in relation to the outcome. Once this phase was completed, Boolean minimization procedures were conducted, utilizing both necessary and sufficient conditions, to identify parsimoni- ous causal pathways for vigilante group formation (Rihoux and Lobe 2009).

Case selection

The first stage of stratification focused on pairing down the potential states from which municipalities would be selected. In this stage, Guerrero and Michoacan were selected. While the formation of vigilante groups is not confined to specific states, Guerrero and Michoacan are the “epicentre… where thousands of armed men par- ticipate in a range of vigilante organisations” (International Crisis Group 2013, p.

1).Insecurity was chosen as the most advantageous factor for selection within the refined geographic area based on its prevalence in the literature as a unifying super- set condition. Using insecurity as the starting point ensured that each case applied to relevant “dimensions within the population of interest” (Seawright and Gerring 2008, p. 296). Focus in this final stage was placed on determining which municipali- ties to select based on measures of insecurity. Data from Mexico’s National Survey of Victimization and Perceptions of Public Security (known as ENVIPE—Encuesta

1 In QCA, the truth table is the workhorse of the analytic moment, detailing all possible configurations of conditions in relation to the outcome.

Nacional de Victimización y Percepción sobre Seguridad Pública) was utilized (INEGI 2012a, b, c). ENVIPE includes a municipal-level survey item that asks respondents whether or not they feel the municipality in which they live is unsafe or not. Municipalities were selected if more than 50% of survey respondents perceived their municipalities as unsafe.

Temporal limitations were placed on the selection of cases to ensure equity in the comparison of cases. Thus, data on insecurity was extracted from the 2012 ENVIPE survey. The key outcome, vigilante formations, was limited to 2013. This strategy was in sync with the events that occurred in Guerrero in Michoacan as 2013 was a boom year for the formation of Mexican vigilante groups (International Crisis Group 2013).

The selection strategy returned 43 municipalities for analysis. Table 1 below pro- vides info on the municipalities as well the percentage of respondents who deemed the municipality unsafe. In addition, a column was included that indicates whether or not the vigilante outcome was observed in 2013. The table indicates that an effec- tive case selection strategy was employed as there is variation in the outcome stem- ming from the stratification procedures.

Model specification Group formation

In each municipality under analysis, the examination of vigilante group formation is limited to the year 2013 to provide for an equivalent analytic period in each case (municipality). Thus, pre-existing groups, such as those that fell under the CRAC banner, are not considered as a group formation event in this analysis. Further, to be considered as a formation event, as opposed to isolated vigilante acts, the following criteria needed to be met based on Johnston (1996): (1) premeditation; (2) voluntary membership by private citizens; (3) an expression of autonomy; (4) the use or threat of force; (5) used in response to threats to an established order; and (6) the goal is security.

Structural equivalence

Activity in the same industry is a good indicator of structural equivalence given that those who operate in the same industry will interact with the same network contacts (Mizruchi 1990). For structural equivalence this research relied on INEGI’s (2012a) National Survey of Occupation and Employment (ENOE—Encuesta Nacional de Ocupación y Empleo). ENOE data was rich with variables that reflected the extent to which a municipality’s residents were structurally equivalent. Selected for this study was 2012 respondent data on job sector employment which was categorized in the following manner: (1) agriculture and livestock; (2) construction; (3) manufac- turing; (4) commerce; (5) services; and (6) other. While job sector is a useful indica- tor, which job sectors hold utility remains to be seen. Thus, inclusion of all available data was deemed the optimal strategy.

Table 1 Municipalities selected for analysis

State Municipality Percentage who feel municipal-

ity is unsafe Vigilante

group forma- tion?

Guerrero Acapulco 84.74 Yes

Guerrero Ajuchitlán del Progreso 94.87 No

Michoacan Álvaro Obregón^a 80.95 No

Michoacán Angangueo 81.25 No

Guerrero Arcelia 68.52 No

Guerrero Atoyac de Álvarez 67.12 Yes

Guerrero Ayutla de los Libres 58.97 Yes

Guerrero Azoyú 70.83 Yes

Michoacán Charo 55.73 No

Guerrero Chilpancingo de los Bravo 66.07 No

Guerrero Copala 60.00 Yes

Guerrero Coyuca de Benítez 67.20 Yes

Guerrero Coyuca de Catalán 78.18 No

Guerrero Cuajinicuilapa 58.23 Yes

Guerrero Cutzamala de Pinzón 83.33 No

Michoacán Hidalgo 65.61 No

Michoacán Huetamo 59.12 No

Guerrero Iguala de la Independencia 74.75 Yes

Michoacán Jacona 66.37 No

Michoacán Jungapeo 60.63 No

Michoacán La Huacana 56.06 Yes

Michoacán La Piedad 70.59 No

Michoacán Lázaro Cárdenas 60.48 No

Michoacán Maravatío 86.11 No

Guerrero Mochitlán 62.75 No

Michoacán Morelia 70.53 No

Guerrero Pungarabato 89.12 No

Guerrero San Miguel Totolapan 95.12 Yes

Michoacán Susupuato 53.66 No

Michoacán Tangancícuaro 58.87 No

Guerrero Técpan de Galeana 80.10 Yes

Guerrero Teloloapan 75.21 Yes

Guerrero Tlacoachistlahuaca 55.91 Yes

Guerrero Tlapa de Comonfort 79.60 Yes

Michoacán Tuxpan 91.04 No

Michoacán Tuzantla 85.62 No

Michoacán Tzintzuntzan 50.37 No

Michoacán Uruapan 57.23 Yes

Michoacán Vista Hermosa 62.67 No

Guerrero Xalpatláhuac 55.56 Yes

Michoacán Zamora 53.49 No

Guerrero Zihuatanejo de Azueta 83.84 No

Michoacán Zitácuaro 78.50 No

Data on the job sector variable was utilized to construct contingency tables for each municipality to determine if structural equivalency applied to 10% or more² of residents under a particular job sector. Each job sector was in essence treated as a separate condition for which the binary variable signified the presence or absence of structural equivalence as operationalized here. If this was the case, structural equiva- lence was coded as a “1” and otherwise coded as a “0” signifying no equivalence (less than 10%) of residents.

Collective efficacy

Arguably the most effective measure of collective efficacy is the actual use of infor- mal social control as opposed to residents’ perceptions of neighbor willingness to engage in such activity (Hipp 2016). In order to measure actualized collective efficacy, this research relied on Mexico’s National Crime Victimization Survey (ENVIPE) which includes questions on whether or not respondents have witnessed neighbors organizing to rectify social problems (e.g. lack of water or gang activity) (INEGI 2013). Rich data was available on community responses to a wide range of issues in 2012 including: (1) water issues; (2) lighting issues; (3) gang activity; and (4) robbery.

As with structural equivalence, which expressions of collective efficacy hold merit in the current analysis remains to be seen. As such, all available indicators were chosen. For each municipality, if at least 10% of respondents reported their neighbors organizing to enact informal social control measures, then the collective efficacy condition was coded as “1” and any percentages less than the cutoff value were coded as “0”.

Police activity

This research examines police activity from a different angle than previous research.

Rather than economic marginalization, its “marginalization from the benefits” con- ferred to others by the police that creates frontier behavior (Goldstein 2003). This logic, coupled with the criminological literature on police presence and its impact on crime guides the inclusion of a variable that addresses police per capita (Shichor et  al. 1980; Chalfin and McCrary 2018). INEGI’s (2012b) National Census of

Table 1 (continued)

a Alvaro Obregon was removed from the analysis as it was the only variable for which indicators of struc- tural equivalence were not present. All conditions utilized in the analysis were present for the remainder of the municipalities samples

2 For both theoretical perspectives 10% was chosen as the cutoff to avoid excluding municipalities that may exhibit the desired activity. Based on the research design, there was no risk of spurious findings based on the selected cutoff as it would have produced pathways with contradictory outcomes and forced the author to test high cutoffs later. Further, there is some support in social consensus research for the use of a 10% cutoff (Xie et al. 2011).

Government, Public Security and State Penitentiary Systems was utilized to gather data on the number of municipal police personnel in each municipality in 2012.

Once obtained, police per 1000 residents was calculated for each municipality. Any police to citizen ratio less than 2 was coded “0” and any ratio greater than or equal to 2 was coded as “1”.

Border

The contagion effect of vigilante group formations may play a role in the forma- tion of other groups. In the case of Nigeria’s Bakassi boys, for example, neighboring areas that heard of the vigilante group’s exploits requested their protection and thus additional branches of the group spread (Harnischfeger 2003). For each municipal- ity, a binary indicator was included that is coded as “1” if the municipality borders another where a vigilante group was active before the start of the period for which group formations are considered (prior to January 1, 2013).

Population density

Following Phillips (2017), population data was included for each municipality. The binary cutoff value for the measures of population density relied upon guidance from the World Bank (2005), which considers rural population density to be less than 150 people per squared kilometer. Those municipalities with fewer than 150 inhabitants per squared kilometer were coded as “0” and those with more were coded as “1”.

Frontier

While frontiers may exist due to the lack of police or police ineffectiveness, these areas may also derive from physical isolation. One manner in which isolation can be measured is each municipality’s road network. Indeed, a municipality’s road net- work is indicative of accessibility (Fafchamps and Shilpi 2008). Any road densities greater than 0.25 km per kilometer squared of municipal surface area were coded as

“1” while any densities lower than this cutoff value were coded as “0”.

Gini coefficient

The Gini coefficient was included for each municipality as a measure of inequality (Phillips 2017). Values greater than or equal to 0.4 were coded as “1” and coef- ficients below this value were coded as “0”. Importantly, this cutoff value was selected based on previous research indicating that Gini coefficients above 0.4 were a potential indicator of instability (Biancotti 2006).

In the following section, the QCA results are presented. Of particular importance, the initial analysis of the complex solution is utilized to reduce the total number of indicators for structural equivalence and collective efficacy as these two condi- tions relied on multiple indicators. Thus, in addition to other goals of the truth table analysis such as examination of contradictory outcomes, this phase was utilized in an exploratory manner to determine which theoretical indicators were most useful

to the research objective. Once this phase of the complex solution was completed, a more parsimonious solution was derived.

Results

With the above operationalized conditions in mind, the analysis began with the examination of necessary conditions. That is, those conditions that are a superset of the outcome of interest. As mentioned in the previous section, the theoretical condi- tions of interest were operationalized widely through the use of several sub-indica- tors. Interestingly, one indicator of collective efficacy, lighting issues, was part of a superset. The structural equivalence indicators did not factor among the superset conditions. Table 2 below shows the results of the analysis of necessity.

The above combinations of conditions are necessary for vigilante group forma- tion and vigilante group formation is sufficient for the presence of these combina- tions. As the inclusion score indicates (inclN), consistency is high, meaning that the specified combinations of conditions are associated with the outcome consistently;

in this case there are no contradictory cases (no municipalities where the outcome was not observed).

While consistency scores are acceptable, the relevance of necessity (RoN) and the coverage (covN) are not indicative of true necessity. The results indicate that two potential OR statements of conditions form a superset that consistently envelops the occurrence of vigilante group formations. This is encouraging as the analysis pro- gresses to sufficient (subset) conditions, but it certainly does not meet the threshold to claim necessity.

This conclusion in large part owes to the even split between the two superset pathways. While the presence of a bordering municipality with a DTO presence is included in both pathways, the “or” joinder (represented by the + sign) indicates that there are exceptions. And indeed, as the analysis of sufficiency will illustrate, the presence of a border is strongly connected with the occurrence of vigilante forma- tions, but there are exceptions. Half the cases of vigilante formation fall under the superset of border presence OR lack of a road network (lowercase variables indicate absence or “0” in the truth table) while the other half fall under the superset relation of a border OR demonstrated collective efficacy for lack of lighting.

Complex solution

The complex solution (all possible combinations of conditions) derived from the truth table included 15 different pathways associated with the formation of vigilante

Table 2 Analysis of necessity inclN RoN covN

BORDER + road.density 1.00 0.423 0.516

BORDER + CE_LIGHT 1.00 0.423 0.516

groups. This multitude owed to the number of conditions included in the initial con- struction of the truth table that reflect collective efficacy and structural equivalency.

Importantly, there were no contradictions. That is, the 15 pathways were exclusively associated with vigilante formations. Despite the need to reduce the number of con- ditions reflecting collective efficacy and structural equivalence, the initial complex solution to the truth table indicated the analysis was on the right path.

Based on this initial examination of subset conditions, the 15 pathways indicate that the presence of a border is an important element (86%) consistent with the ear- lier discussion of necessity. In addition, lower population densities were included more often than their high-density counterpart, though there are important qualifica- tions to this discussed later. High road density and high Gini coefficients were also present in at least 60% of the pathways.

The complex solution indicated which theoretically derived conditions were good candidates moving forward with a parsimonious solution. Structural equivalency in the agricultural sector was the most prevalent (66%) in the initial pathways while the services industry was present in only two. Other indicators such as construction and manufacturing were largely absent. Demonstrated collective efficacy in response to a lack of lighting was by far the most prominent measure of collective efficacy present in the basic pathways. In fact, this measure was in each of the basic pathways save two, consistent with the analysis of necessity.

Moving forward, collective efficacy for lighting issues and structural equivalence in the agricultural sector were selected. The truth table analysis was repeated as performed previously with the refined set of indicators. While the original complex solution was positive, given the complete absence of contradictions, the questions moving forward was whether or not the refined conditions for structural equivalency and collective efficacy would demonstrate the same utility.

Boolean minimization

With the number of potential conditions reflecting collective efficacy and struc- tural equivalency reduced, Boolean minimization was conducted to arrive at a parsimonious solution for the vigilante formation outcome. This procedure was accomplished using row dominance and the directional expectation that con- ditions reflecting either structural equivalence or collective efficacy would be present. There are a number of Boolean minimization techniques available for

Table 3 Parsimonious solution

inclS PRI covS covU

BORDER*gini.coefficient 1.00 1.00 0.312 0.125

BORDER*ROAD.DENSITY*CE_LIGHT 1.00 1.00 0.625 0.438

POP_DENSITY*road.density*GINI.COEFFICIENT 1.00 1.00 0.125 0.125

POLICE*road.density*SE_AGRICULTURE*CE_LIGHT 1.00 1.00 0.125 0.125

M1 1.00 1.00 1.00

QCA, this author opted for the enhanced Quine-McCluskey algorithm (Dusa and Thiem 2015). This procedure coupled with the refined set of conditions resulted in more parsimonious pathways. Table 3 below shows each set of conditions for the parsimonious solution.

As indicated in the sufficiency inclusion score for each set of conditions, con- sistency for these pathways is excellent as none of them have any contradictory outcomes; only the formation of vigilante groups is associated with these path- ways. Regarding the first pathway, presence of a vigilante group in the border- ing municipality and (signified by asterisks) a low Gini coefficient (< 0.4), was sufficient for vigilante group formation. This combination of factors had low unique coverage, meaning it is present in conjunction with other pathways. In particular, this combination of conditions was associated with the outcome in four municipalities (hence the sufficiency coverage score of 0.312).

In the second pathway, the presence of a neighboring municipality with a vig- ilante group, coupled with high road density and previously demonstrated group efficacy to solve municipal lighting problems, had both the highest coverage in terms of sufficiency and uniqueness. This set of conditions was present in six vigilante group formations (covS = 0.625) and was uniquely associated with four cases.

The third pathway features a combination of high population density (> 150 people per km²), low road density and a high Gini coefficient. This particu- lar condition set had the same coverage for both sufficiency and uniqueness.

Accordingly, it was found to be a unique subset condition for two cases of the outcome. Similarly, the fourth and final pathway was a unique subset condition for two cases. That is, the combination of higher rates of police (≥ 2 per 1000 citizens), low road density (< 0.25  km of roads per km²of municipal surface area), the presence of at least 10% of the population involved in the same indus- try and demonstrated collective efficacy to solve lighting issues was uniquely sufficient in two municipalities.

Reducing the number of indicators reflecting the presence of realized collec- tive efficacy and structural equivalency greatly reduced the number of pathways in the parsimonious solution. As a result, four different pathways were derived from the analysis. Interestingly, the results bolster the assertion made earlier in this analysis, and alluded to the in the literature, that a multi-conjunctural approach is necessary to understand the formation of vigilante groups, even within a similar physical and temporal context.

In examining the role of collective efficacy and structural equivalence in vigi- lante group formation, the pathways support the theoretical asserts of collective efficacy. In fact, the pathway that included demonstrated collective efficacy was the strongest pathway in terms of coverage and uniqueness. Limited support for structural equivalence is provided in the fourth pathway, though it occurs along- side collective efficacy. In the following section, these results are placed in theo- retical context, utilizing the extant literature to better understand the contribu- tion of the current work. Further, the Mexican context is discussed and how this impacts our understanding of the phenomenon of vigilante groups.

Discussion

Before delving into the discussion, certain shortcomings of the present study must be mentioned. Perhaps most importantly, the study was limited to identify- ing relevant conditions and pathways, which circumvented the different socio-cul- tural contexts in Guerrero and Michoacan. For example, Guerrero has a long his- tory of locally embedded self-defense groups and the UPOEG was already active in the state before 2013. Yet some groups chose to affiliate with UPOEG while others, such as in Coyuca de Benítez, formed in a more isolated context (“Crean”

2013). In contrast to Guerrero, the state of Michoacan featured group formations that were not always “homegrown” as members of the burgeoning self-defense movement went from one town to the next to foment the creation of new groups.

Equally important is to apply other types of analysis to this topic. While QCA has demonstrated value in extracting causal pathways, the dichotomization of events and conditions may obscure some relationships (Hellström 1998).

With the above limitations in mind, future research should incorporate spe- cific contextual factors into causal pathways and conditions to fully understand that factors that promote the formation of these groups. These antecedent condi- tions can also be examined in light of the relative success, in some cases, of these groups. Not only have they kicked criminal groups out of certain towns, but their motivations are, at least in some occasions, altruistic. This in no doubt owes to the local makeup of many of these groups who have all faced the same problem, together, for far too long (Guerrero Gutiérrez 2014).

Wealth distribution as a binding factor

The first pathway identified in the parsimonious solution was the presence of a bordering municipality with a vigilante group and a low Gini coefficient (i.e. bet- ter wealth distribution). This pathway can be characterized as collective action catalyzed by wealth distribution. This was the simplest pathway as it only con- tained two conditions unique to vigilante group formations. While this pathway was parsimonious, its unique coverage was low.

It is noteworthy that better distribution of a municipality’s wealth is part of the shortest pathway. As Phillips (2017) noted, income inequality is accompanied by security inequality. Indeed, income inequality as measured through the Gini coef- ficient has been shown to adversely affect collective action (Bruce and Thorn- ton 2004). Previous research suggests that as wealth is more evenly distributed, people are encouraged to “participate in social activities, to cooperate in various collective action problems, or to contribute to public goods and services” (Bard- han et al. 2007, p. 1844). This particular characteristic of the pathway merits fur- ther qualitative study, particularly field research, to better understand what types of community activity are conducive to other collective responses in particular contexts.

Of further interest was the choice of binary cutoff, as this pathway reflects Gini coefficients below the critical value of 0.4. Anything higher (fewer people controlling more wealth) is a sign of potential instability (Biancotti 2006). This pathway reinforces the notion that wealth distribution is a binding factor that can catalyze the formation of vigilante groups. However, based on the results of this research it’s not likely to be a common scenario that drives such activity in Mexico.

Dense isolation

While better wealth distribution was present in the previous pathway, the opposite, a Gini coefficient above the critical cutoff of 0.4 was present in another pathway. This lack of wealth distribution was present alongside isolation as indicated by low road density in conjunction with high population density. This interesting combination of conditions speaks directly to the role that wealth in the hands of a few can play in the formation of vigilante groups, given the proper context.

As with the previous pathway, this particular set of conditions was present in only two cases and unique to only one case of vigilante formation. The two municipali- ties that corresponded to this pathway were Iguala, Guerrero and Uruapan, Michoa- can. In the former municipality, this was a unique combination of conditions. How- ever, amongst the municipalities with vigilante formations, high population density was rare (12%). In contrast, in municipalities where no vigilante formations were identified, high population density was present in 27% of cases. The latter percent of cases is still low, but double that of the areas where the outcome was observed.

This pathway also bolsters the notion that isolation and density of inhabitants work together to overcome the collective action problem presented by wealth inequality. In the Mexican context, there was no doubt that businesspersons in various sectors (e.g., lime and avocado growers) supported the formation of these groups given the pressure placed on them by organized crime (Nateras González 2017). In some cases, the lead- ers of these groups were able to provide monetary compensation so that younger inhab- itants would join these informal social control efforts (García Ramírez and Martínez 2014). In other cases in both Guerrero and Michoacán, wealthy business owners have openly voiced their support for the vigilantes; some have even been attacked for doing so (Beauregard 2014).

The aforementioned pathways reinforce the antecedent conditions discussed in the literature. However, the final two pathways bolster the assertion made in this research that collective efficacy and structural equivalence are two theories that can explain the emergence of these groups. In terms of coverage, the results of the QCA indicate that collective efficacy is the most applicable theoretical perspective. Indeed, in the one pathway where structural equivalency appears as a sufficient condition, it is accompa- nied by demonstrated collective efficacy.

Non‑isolated collective efficacy

The first pathway featuring demonstrated collective efficacy to address lighting concerns also included high road density and a border with a municipality that had vigilantism. In this author’s estimation, it is no coincidence that the border variable was one of the conditions included in the pathway. Within the Mexi- can context, it has been amply described how vigilante groups moved to other municipalities to catalyze the formation of more groups, but neither the litera- ture nor journalistic accounts help to explain the intervening mechanisms that translate into the adoption of similar activity occurring in bordering municipali- ties. Collective efficacy, as operationalized here as the previous demonstration of organized community activity to resolve a collective issue is one such intervening mechanism.

Another important reason why collective efficacy may have utility is that par- ticipating in vigilantism involves a great deal of risk to community members.

The implication is that, in many communities, the decision to confront crime and violence due to perceived vulnerability will cause increased risk as criminal groups readjust to changing attitudes of the citizenry (García Ramírez and Mar- tínez 2014). Perhaps it is for this reason that the indicator for lighting issues was the most promising indicator in the initial complex analysis. Joining together for this issue certainly would have involved less risk while signaling to others that working together and achieving collective efficacy was quite possible on riskier ventures.

However, for collective efficacy to develop into “the assurance that an estab- lished system of order will prevail” (Johnston 1996, p. 231) information must spread to others. The dense roads catalyzed more interaction and more informal information gathering between residents. This aids in the transfer of informal activity into other sectors of citizen involvement. Previous research on neigh- borhood watch organizations supports this finding. As Wells et al. (2006) assert,

“people are more likely to contact a community group in response to a problem when they reside in areas with…people who are aware of community groups” (p.

538).

Equivalent efficacy

The fourth and final pathway involves both theoretical indicators of interest in conjunction with physical isolation, in contrast to the previous pathway. The most striking condition, however, is the presence of at least 2 police per 1000 citizens.

Abrahams (1998) placed vigilante group formation within the context of frontier zones, where the state fails to maintain control over illegitimate uses of violence.

Important in this conception of frontier zones is that they can arise both in the presence and absence of the state.

This police presence relates to what Omach (2010) called the “ambiguous nature of authority in peripheral areas” (p. 432). Not only can police authority

be ambiguous, but previous studies indicate that a negative relationship exists between satisfaction with the police and calling the police for assistance (Wells et al. 2006). What is likely in the context of this study is that in isolated commu- nities police will be isolated as well.

It is important to reemphasize the presence of these variables within a preexist- ing contest of insecurity. Thus, the juxtaposition of higher police-citizen ratios, and ongoing insecurity can create tension. Indeed, police presence as measured through size and activity does not necessarily impact the fear of crime (Hauser and Kleck 2017).

However, of further importance to the isolation of communities is the interplay with structural equivalency. In the previous pathway collective efficacy worked in conjunction with a dense road network. This pathway, however, demonstrates that equivalency may overcome this structural isolation. As discussed in the overview of this theoretical perspective, structural equivalence causes similarly situated people to behave in similar ways without knowledge of the way others act. Thus, the inter- section of similarly situated actors and crime may promote similarity in attitude and action that catalyzes vigilante group formation when efficacy is present.

This research demonstrated that both collective efficacy and structural equiva- lence are important theoretical perspectives that help explain the emergence of vigi- lante groups. Non-isolated collective efficacy had the highest uniqueness and great- est coverage among the different pathways. Other explanations, such as security inequality, are still quite credible and important to the understanding of the emer- gence of these groups as the results of this analysis highlight. Hybrid theoretical explanations that combine social interaction dynamics and socio-structural charac- teristics hold great promise in furthering academic understanding of why citizens opt to take the law into their own hands.

Understanding this phenomenon through a theoretical lens is necessary for pre- ventive efforts. By understanding antecedent conditions, more accurate projec- tions can be made, and policy efforts better focused. Future research should include larger scale studies with results that may be generalized to larger populations. While the results of this study shed important light on the formation of vigilante groups, the sample was focused on a particular region making such generalizations diffi- cult. Further, while focus on this research was given to the formation of organized groups, ad hoc citizen formations should also be incorporated under the hybrid theo- retical umbrella.

Funding The author received no funding for this research.

Data availability Data will be made available upon request.

Code availability Upon request; all coding conducting in the R statistical environment.

Declarations

Conflict of interest There are no conflicts of interest presented by this research.

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