Review
Effect of drug law enforcement on drug market violence: A systematic review

https://doi.org/10.1016/j.drugpo.2011.02.002Get rights and content

Abstract

Violence is amongst the primary concerns of communities around the world and research has demonstrated links between violence and the illicit drug trade, particularly in urban settings. Given the growing emphasis on evidence-based policy-making, and the ongoing severe drug market violence in Mexico and other settings, we conducted a systematic review to examine the impacts of drug law enforcement on drug market violence. We conducted a systematic review using Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines. Specifically, we undertook a search of English language electronic databases (Academic Search Complete, PubMed, PsycINFO, EMBASE, Web of Science, Sociological Abstracts, Social Service Abstracts, PAIS International and Lexis-Nexis), the Internet (Google, Google Scholar), and article reference lists, from database inception to January 24, 2011. Overall, 15 studies were identified that evaluated the impact of drug law enforcement on drug market violence, including 11 (73%) longitudinal analyses using linear regression, 2 (13%) mathematical drug market models, and 2 (13%) qualitative studies. Fourteen (93%) studies reported an adverse impact of drug law enforcement on levels of violence. Ten of the 11 (91%) studies employing longitudinal qualitative analyses found a significant association between drug law enforcement and drug market violence. Our findings suggest that increasing drug law enforcement is unlikely to reduce drug market violence. Instead, the existing evidence base suggests that gun violence and high homicide rates may be an inevitable consequence of drug prohibition and that disrupting drug markets can paradoxically increase violence. In this context, and since drug prohibition has not meaningfully reduced drug supply, alternative regulatory models will be required if drug supply and drug market violence are to be meaningfully reduced.

Section snippets

Background

Violence is amongst the primary concerns of communities around the world, and the illegal drug trade has been identified as a key cause of violence, particularly in urban areas (Johnson et al., 2000, Martin et al., 2009, Ousey and Lee, 2004, Romero-Daza et al., 2003). Whilst drug market violence has traditionally been framed as resulting from the effects of drugs on individual users (e.g., violence stemming from drug-induced psychosis), violence is increasingly being understood as a means used

Methods

This review involved conventional systematic searching, data extraction and synthesis methods. Specifically, a comprehensive search of the literature was undertaken using electronic databases (Academic Search Complete, PubMed, PsycINFO, EMBASE, Web of Science, Sociological Abstracts, Social Science Abstracts, PAIS International and Lexis-Nexis), the Internet (Google, Google Scholar), and article reference lists. Search terms included “violence,” “drug-related violence,” “drug market violence,”

Study selection and study characteristics

In the initial search, 314 potential articles were identified for inclusion in the review. Of these, 48 (15.3%) were excluded because they did not present new data (e.g., editorials). As such, 266 (84.7%) articles were retrieved for detailed examination after initial searching of keywords and abstracts. Of these, 248 (93.2%) were deemed non-relevant to the current review for the following reasons: 179 (67.3%) were excluded based on a lack of explicit mention of violence in the analysis, whilst

Discussion

In this systematic review, all available English language studies that evaluated the association between drug law enforcement and violence were reviewed. Whilst the number of studies was limited, they included a diverse array of literature including longitudinal analyses involving up to 6 years of prospective follow-up, regression analyses, qualitative analyses, and mathematical predictive models. Contrary to our primary hypothesis, amongst studies that systematically evaluated this question

Contributors

Evan Wood had full access to all the data in the study and had final responsibility for the decision to submit for publication. DW and GR conducted the systematic search. DW and EW drafted the manuscript. GG and TK revised the systematic review and meta-analysis methodology. TK, JM and GG revised the manuscript substantially. All authors have seen and approved the final version.

Funding

Dan Werb is supported by the Canadian Institutes of Health Research. Further support is provided CIHR Team Grant RAA-79918.

The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.

Conflict of interest statement

Dan Werb, Greg Rowell, Gordon Guyatt, Thomas Kerr and Evan Wood have no competing interests to declare. Julio Montaner has received grants from, served as an ad hoc adviser to, or spoken at events sponsored by Abbott, Argos Therapeutics, Bioject Inc., Boehringer Ingelheim, BMS, Gilead Sciences, GlaxoSmithKline, Hoffmann-La Roche, Janssen-Ortho, Merck Frosst, Panacos, Pfizer Ltd., Schering, Serono Inc., TheraTechnologies, Tibotec (JandJ), and Trimeris.

Acknowledgments

The authors would like to thank study authors for providing detailed responses to our requests for additional data. The authors would also like to thank Deborah Graham, Peter Vann and Brandon Marshall for administrative and design assistance.

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