True Believers, Deserters, and Traitors

• Date: 01 August 2015
• Author: Ben Oppenheim,Michael Weintraub,Juan F. Vargas,Abbey Steele
• Published date: 01 August 2015
• DOI: 10.1177/0022002715576750
• Subject Matter: Articles

Article

True Believers,

Deserters, and Traitors:

Who Leaves Insurgent

Groups and Why

Ben Oppenheim

1,2

, Abbey Steele

3

, Juan F. Vargas

4

,

and Michael Weintraub

5

Abstract

Anti-insurgent militias and states attempt to erode insurgent groups’ capacities and

co-opt insurgent fighters by promising and providing benefits. They do so to create a

perception that the insurgency is unraveling and to harness inside information to

prosecute more effective counterinsurgency campaigns. Why do some insurgents

defect to a paramilitary group and others exit the war by demobilizing, while still

others remain loyal to their group? This article presents the first empirical analysis of

these questions, connecting insurgents’ motivations for joining, wartime experi-

ences, and organizational behavior with decisions to defect. A survey of

ex-combatants in Colombia shows that individuals who joined for ideological rea-

sons are less likely to defect overall but more likely to side-switch or demobilize

when their group deviates from its ideological precepts. Among fighters who joined

for economic reasons, political indoctrination works to decrease their chances of

demobilization and defection to paramilitaries, while opportunities for looting

decrease economically motivated combatants’ odds of defection.

1

Center on International Cooperation, New York University, New York, NY, USA

2

Center on International Conflict and Negotiation, Stanford University, Stanford, CA, USA

3

Department of Political Science, University of Amsterdam, Amsterdam, the Netherlands

4

Department of Economics, Universidad del Rosario, Bogota

´, Colombia

5

Department of Political Science, Binghamton University (SUNY), Binghamton, NY, USA

Corresponding Author:

Ben Oppenheim, New York University Center on International Cooperation, 726 Broadway, Suite 543,

New York, NY 10003, USA.

Email: benoppenheim@nyu.edu

Journal of Conflict Resolution

2015, Vol. 59(5) 794-823

ªThe Author(s) 2015

Reprints and permission:

sagepub.com/journalsPermissions.nav

DOI: 10.1177/0022002715576750

jcr.sagepub.com

Keywords

militias, civil wars, side switching, internal armed conflict, demobilization, insurgency,

ideology, defection, Colombia

Multiparty civil wars—armed conflicts that feature more than one armed non-state

actor—constituted a third of civil wars between 1816 and 2007 and have become

more common over time (Christia 2012). Most of these conflicts have involved

anti-insurgent paramilitaries: in nearly two-thirds of civil wars since 1989,

governments have used militias for counterinsurgency (Stanton 2015).

1

Recent

work seeks to explain the emergence of militias (e.g., Carey, Colaresi, and Mitchell

2015; Eck 2015), investigate their impact on violence (e.g., Cohen and Norda

˚s 2015;

Stanton 2015), and explore how states interact with them (e.g., Staniland 2015; for

excellent case studies of paramilitaries, see Romero 2003, Staniland 2012a,

Schubiger 2012, and Jentzsch 2012). This article contributes to our understanding

of who joins paramilitaries (Humphreys and Weinstein 2008; Arjona and Kalyvas

2011; Forney 2015). Specifically, we ask who abandons insurgent groups to fight

with these militias a nd who instead opts to demobiliz e, leaving the conflict

altogether.

Recent research on the micro-foundations of civil war has shed light on who joins

insurgents and counterinsurgent militias (e.g., Weinstein 2007; Humphreys and

Weinstein 2008; Daly 2012; Forney 2015). These factors include poverty, lack of

access to education, political alienation, and embeddedness in social networks that

facilitate recruitment. In Colombia, scholars have also drawn on surveys of ex-

combatants to answer a related but distinct question, that is, among those

willing to fight, what explains who joins insurgents versus paramilitaries? Arjona

and Kalyvas (2011) find that all fighters are similarly poor and aggrieved and that

the best indicator of which side joined is group presence in the recruit’s community.

Ugarriza and Craig (2013) find that ex-combatants who favor leftist ideology and

have families that supported leftist political parties are much more likely than a para-

military group to have been members of an insurgent group.

If we know something about who fights, we lack similar evidence about who

becomes a traitor to their cause. Combatants can abandon their armed group in a

variety of different ways. Here we focus on the following two: side-switching and

demobilization. We define side-switching as leaving an armed group to fight for

another group representing a different ideological or ethnic constituency. We define

individual demobilization as leaving an armed group and exiting the war with the

promise of receiving benefits from the government, typically in exchange for

information.

Although the defection of fighters from one armed group to another is common

(Kalyvas 2008), civil war scholars have not established clear causal mechanisms that

explain what drives individual combatants to leave their armed groups or to fight for

(formerly) opposing militias (see also Rosenau et al. 2014). Such side-switching is

Oppenheim et al. 795