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Search Result: 47 Records found
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Focused deterrence strategies effects on crime
  • Authors Anthony A. Braga, David L. Weisburd, Brandon Turchan
  • Published date 2019-09-09
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/full/10.1002/cl2.1051
  • English

    PLAIN LANGUAGE SUMMARY

    Focused deterrence is associated with moderate reductions in crime

    A relatively small number of groups and persons are responsible for a disproportionate share of crime. Focused deterrence strategies attempt to reduce offending behaviour for specific types of crime. These strategies are associated with moderate overall reductions in crime.

    Crime is not displaced to other areas, rather it is more likely that there is a diffusion of crime control benefits to adjacent areas and similar people and groups.

    What is this review about?

    Focused deterrence strategies combine law enforcement, community mobilisation, and social services in an attempt to reduce offending behaviour for specific crime types. A key feature of this crime control strategy is that the consequences of continued criminal offending and available social services are directly communicated to targeted subjects.

    This review examines the relationship between focused deterrence policing and crime, and gives consideration to the different types of focused deterrence strategies and programme evaluation designs.

    What is the aim of this review?

    This Campbell systematic review examines the effects of focused deterrence policing on crime. The review summarises and analyses results from 24 quasi-experimental evaluations of focused deterrence interventions, including 12 programmes targeting criminally active gangs or groups, nine programmes targeting open-air drug markets, and three programmes targeting high-risk individual offenders. All but one of the studies are from the USA.

    What studies are included?

    A total of 24 studies of focused deterrence policing interventions were identified. All studies were published from 2001 to 2015. Twenty-three studies were conducted in the USA and one in Scotland. None of the identified studies used a randomised controlled trial design.

    What are the main findings of this review?

    Is focused deterrence an effective approach to reducing criminal offending among problem persons and groups?

    Yes. The available evidence suggests an overall reduction in crime when focused deterrence strategies are used. The largest reductions are generated by focused deterrence programmes that target criminally active gangs or groups, followed by interventions that target chronic individual offenders and drug market interventions.

    Do some programmes work better than others?

    Yes. Gang/group intervention programmes have the largest effect, followed by the high-risk individuals programmes, with the smallest effect from drug market intervention (DMI) programmes. DMI programmes are most likely to suffer implementation problems, which reduce effectiveness.

    Does crime get displaced to other areas?

    No. No studies found significant crime displacement effects into surrounding areas. There is some evidence of the diffusion of crime control benefits.

    What do the findings of the review mean?

    Findings from this review support the growing use of focused deterrence as a proactive crime reduction strategy. Practitioners and policymakers should continue to implement focused deterrence programmes to address serious crime problems.

    The number of studies included in the updated review is more than double the number of studies included in the previous iteration of the review. However, despite the increase in eligible studies, no evaluations utilised a randomised controlled trial design. The growth of focused deterrence warrants more methodologically rigorous programme evaluations and further exploration into the specific components of the strategy, to improve our understanding into how the programme reduces crime.

    How up-to-date is this review?

    The review authors searched for studies up to October 2015.

Disorder policing to reduce crime
  • Authors Anthony Braga, Brandon Welsh, Cory Schnell
  • Published date 2019-09-09
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.1002/cl2.1050
  • English

    PLAIN LANGUAGE SUMMARY

    Policing disorder through community and problem-solving policing is associated with reductions in crime, but aggressive, order maintenance approaches are not

    Disorderly conditions are seen as a precursor to more serious crime, fear of crime, and neighbourhood decline. Policing disorder is associated with reductions in crime, but only when community and problem-solving tactics are used. Aggressive, order maintenance based approaches are not effective.

    What is the aim of this review?

    This Campbell systematic review examines the effects of disorder policing interventions on crime. The review summarises evidence from 28 high-quality studies (representing 30 independent tests), including nine randomised controlled trials. Most the studies come from the USA.

    What is this review about?

    Policing social and physical disorderly conditions is rooted in the broken windows approach: disorder is a precursor to more serious crime, fear of crime, and neighborhood decline. Addressing disorder has become a central fixture of policing, especially in the USA. Yet, evaluations of the effectiveness of disorder policing strategies in controlling crime yield conflicting results.

    Policing disorderly conditions can be divided into two main strategies: (1) Order maintenance or zero tolerance policing, where police attempt to impose order through strict enforcement; and (2) Community policing and problem-solving policing, where police attempt to produce order and reduce crime through cooperation with community members and by addressing specific recurring problems.

    This review examined the effects of disorder policing strategies compared to traditional law enforcement actions (e.g., regular levels of patrol) on the rates of crime, including property crime, violent crime, and disorder/drug crime. This review also examined whether policing disorder actions at specific locations result in crime displacement (i.e., crime moving around the corner) or diffusion of crime control benefits (i.e., crime reduction in surrounding areas).

    What studies are included?

    A total of 28 disorder policing studies (representing 30 independent tests) met the criteria to be included in this review. The studies spanned the period from 1985 to 2012, and were mostly carried out in the USA. All of the studies used high-quality designs to evaluate the impact of the intervention; nine were randomised controlled trials. Twelve tests were completed in large cities (more than 500,000 residents), nine tests were completed in medium-sized cities (200,000 to 500,000 residents), and the other nine tests were completed in smaller cities. All of the tests were carried out in specific geographical settings, including small places (e.g., crime hot spots and problem buildings), smaller police-defined areas (e.g., patrol beats), neighbourhoods and selected stretches of highways, and larger police-defined areas (e.g., precincts and divisions).

    What are the main findings of this review?

    Do policing interventions focused on disorderly conditions reduce crime?

    Yes, in addition to an overall reduction in crime, there is a reduction in property crime, violent crime, and disorder/drug crime when disorder policing interventions are implemented.

    Do policing interventions focused on disorder result in crime being displaced or crime control benefits being diffused to surrounding areas?

    Disorder policing interventions are associated with diffusion of crime control benefits in areas surrounding targeted locations. This conclusion is based on 15 tests that measured displacement or diffusion effects.

    Of the two main strategies used in policing disorder, is one more effective than the other?

    Yes, policing disorder through community and problem-solving is associated with reductions in crime. Aggressive, order maintenance approaches are not effective.

    What do the findings of the review mean?

    The types of strategies used by police departments to address disorderly conditions seem to matter in controlling crime, and this holds important implications for police-community relations, justice, and crime prevention. Further research is needed to understand the key programmatic elements that maximise the capacity of these strategies

    How up-to-date is this review?

    This review includes studies completed before 2013.

Hot spots policing of small geographic areas effects on crime
  • Authors Anthony A. Braga, Brandon Turchan, Andrew V. Papachristos, David M. Hureau
  • Published date 2019-09-08
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/full/10.1002/cl2.1046
  • English

    PLAIN LANGUAGE SUMMARY

    Hot spots policing is associated with reductions in crime

    Hot spots policing is associated with small but meaningful reductions in crime at locations where criminal activities are most concentrated. Focusing police efforts at high activity crime places is more likely to produce a diffusion of crime prevention benefits into areas adjacent to targeted hot spots than crime displacement.

    What is this review about?

    Crime is concentrated in small places, or "hot spots," that generate half of all criminal events. Hot spots policing focuses police resources and attention on these high crime places. For the purpose of this review, hot spots programs must have consisted of police-led crime prevention efforts that targeted high-activity crime "places" rather than larger areas such as neighborhoods.

    This review considers both randomized controlled experimental and quasi-experimental evaluations of the effects of hot spots policing interventions on crime where the control group in each study received routine levels of traditional police enforcement tactics.

    What is the aim of this review?

    This Campbell systematic review assesses the preventive effects of focusing police efforts on crime "hot spots" as compared to traditional police crime control strategies.  The review summarises evidence from 65 studies containing 78 tests of hot spots policing interventions, including 27 randomized controlled trials and 38 quasi-experimental evaluations.

    What studies are included?

    A total of 65 studies containing 78 tests of hot spots policing interventions were identified. However, standardized effects sizes were only calculated for 73 main effects tests due to reporting deficiencies in three included studies.

    All studies were published from 1989 to 2017: 51 studies were conducted in the USA, four in the UK, four in Sweden, and six in other countries.

    What are the main findings of this review?

    Does focusing crime prevention efforts on crime hot spots reduce crime?

    Yes. Hot spots policing generates statistically-significant small reductions in overall crime and disorder in areas where the strategy is implemented.

    These crime control gains were evident across specific categories of crime outcomes including drug offenses, disorder offenses, property crimes, and violent crimes.

    Does policing crime hot spots inevitably produce crime displacement effects?

    No. Overall, it is more likely that hot spots policing generates crime control benefits that diffuse into the areas immediately surrounding the targeted locations than displacing crime into nearby locations.

    What do the findings of the review mean?

    Findings from this review support hot spots policing as a proactive crime reduction strategy. Police departments should incorporate focusing resources at high-activity crime places as part of their broader approach to crime prevention.

    The majority of studies included in the updated review have been published since the previous iteration of the review and utilized rigorous research designs.

    Despite the drastic increase in eligible studies, only one study conducted a formal cost-benefit assessment of the hot spot policing intervention. The growth of hot spots policing warrants further empirical attention on the efficiency of hot spots policing for reducing crime.

    How up-to-date is this review?

    The review authors searched for studies up to February 2017.

Cognitive-behavioural treatment for amphetamine-type stimulants (ATS)-use disorders
  • Authors Takayuki Harada, Hiroshi Tsutomi, Rintaro Mori, David Wilson
  • Published date 2019-07-25
  • Coordinating group(s) Crime and Justice
  • Type of document Review
  • See the full review https://onlinelibrary.wiley.com/doi/10.1002/cl2.1026
  • English

    PLAIN LANGUAGE SUMMARY

    Cognitive‐behavioural treatment for amphetamine‐type stimulants‐use disorders

    What was the aim of this review?

    The aim of this Cochrane review was to find out whether cognitive‐behavioural treatment (CBT) is effective to treat people with amphetamine‐type stimulants (ATS)‐use disorders. Researchers in the Drugs and Alcohol Group of Cochrane collected and analysed all relevant studies to answer this question and found two studies.

    Key messages

    The current evidence was inadequate to draw any firm evidence‐based treatment recommendations for the client population.

    What was studied in the review?

    ATS are a group of synthetic stimulants and their use has been widespread globally. These types of drugs are highly addictive and prolonged use may result in a series of mental and physical symptoms including anxiety, confusion, insomnia (difficulty sleeping), mood disturbances, cognitive impairments (difficulty thinking and understanding), paranoia (irrational feeling that people are 'out to get you'), hallucinations (where someone experiences something that does not exist outside their own mind) and delusion (a mistaken belief).

    Currently there is no widely accepted treatment for ATS‐use disorder. However, CBT is often the first choice of treatment. It is a psychological treatment (talking therapy) approach to modify distorted thoughts and beliefs, and maladaptive behaviours (things that people do to stop them from adjusting to situations). The effectiveness of CBT for other substance‐use disorders (e.g. alcohol‐, opioid‐ and cocaine‐use disorders) has been well documented and as such this basic treatment approach has been applied to the ATS‐use disorder. These types of therapies are expected to prevent relapse and decrease drug use.

    What are the main results of the review?

    The review authors found two eligible studies. Both studies were conducted in Australia. One study compared a single session of brief CBT to a waiting‐list control where participants received no treatment during the study period. One study compared web‐based CBT to a waiting‐list control. Both studies were funded by the Australian Government of Health and Ageing.

    The review showed that when participants received CBT, compared to waiting‐list control, there was no difference. There was insufficient evidence to conclude that CBT was effective or ineffective at treating ATS‐use disorders.

    How up‐to‐date is this review

    The review authors searched for studies that had been published up to July 2018.

Effects of bystander programs on the prevention of sexual assault among adolescents and college students: A systematic review
  • Authors Heather Hensman Kettrey, Robert A. Marx, Emily E. Tanner-Smith
  • Published date 2019-01-04
  • Coordinating group(s) Crime and Justice
  • Type of document Review
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2019.1
  • English

    PLAIN LANGUAGE SUMMARY

    Bystander programs increase bystander intervention but no effect on perpetrating sexual assault

    Bystander sexual assault prevention programs have beneficial effects on bystander intervention but there is no evidence of effects on sexual assault perpetration. Effects on knowledge and attitudes are inconsistent across outcomes.

    What is this review about?

    Sexual assault is a significant problem among adolescents and college students across the world. One promising strategy for preventing these assaults is the implementation of bystander sexual assault prevention programs, which encourage young people to intervene when witnessing incidents or warning signs of sexual assault. This review examines the effects bystander programs have on knowledge and attitudes concerning sexual assault and bystander behavior, bystander intervention when witnessing sexual assault or its warning signs, and participants’ rates of perpetration of sexual assault.

    What is the aim of this review?

    This Campbell systematic review examines the effects of bystander programs on knowledge and attitudes concerning sexual assault and bystander intervention, bystander intervention when witnessing sexual assault or its warning signs, and the perpetration of sexual assault. The review summarizes evidence from 27 high‐quality studies, including 21 randomized controlled trials.

    What studies are included?

    This review includes studies that evaluate the effects of bystander programs for young people on (a) knowledge and attitudes concerning sexual assault and bystander intervention, (b) bystander intervention behavior when witnessing sexual assault or its warning signs, and (c) perpetration of sexual assault. Twenty‐seven studies met the inclusion criteria. These included studies span the period from 1997 to 2017 and were primarily conducted in the USA (one study was conducted in Canada and one in India). Twenty‐one studies were randomized controlled trials and six were high quality quasi‐experimental studies.

    What are the main findings of this review?

    Do bystander programs have an effect on knowledge/attitudes, on bystander intervention, or on sexual assault perpetration?

    Bystander programs have an effect on knowledge and attitudes for some outcomes. The most pronounced beneficial effects are on rape myth acceptance and bystander efficacy outcomes. There are also delayed effects (i.e., 1 to 4 months after the intervention) on taking responsibility for intervening/acting, knowing strategies for intervening, and intentions to intervene outcomes. There is little or no evidence of effects on gender attitudes, victim empathy, date rape attitudes, and on noticing sexual assault outcomes.

    Bystander programs have a beneficial effect on bystander intervention. There is no evidence that bystander programs have an effect on participants’ rates of sexual assault perpetration.

    What do the findings of this review mean?

    The United States 2013 Campus Sexual Violence Elimination (SaVE) Act requires postsecondary educational institutions participating in Title IX financial aid programs to provide incoming college students with sexual violence prevention programming that includes a component on bystander intervention.

    Bystander programs have a significant effect on bystander intervention. But there is no evidence that these programs have an effect on rates of sexual assault perpetration. This suggests that bystander programs may be appropriate for targeting the behavior of potential bystanders but may not be appropriate for targeting the behavior of potential perpetrators.

    Beneficial effects of bystander programs on bystander intervention were diminished by 6 months post‐intervention. Thus, booster sessions may be needed to yield any sustained effects.

    There are still important questions worth further exploration. Namely, more research is needed to investigate the underlying causal mechanisms of program effects on bystander behavior (e.g., to model relationships between specific knowledge/attitude effects and bystander intervention effects), and to identify the most effective types of bystander programs (e.g., using randomized controlled trials to compare the effects of two alternate program models). Additionally, more research is needed in contexts outside of the USA so that researchers can better understand the role of bystander programs across the world.

    How up‐to‐date is this review?

    The review authors searched for studies up to June 2017.

  • Spanish

    RESUMEN EN LENGUAJE SENCILLO

    Los programas contra la omisión de socorro para transeúntes aumentan su intervención, pero no afectan la incidencia de las agresiones sexuales

    Los programas de prevención de agresiones sexuales para crear conciencia en los transeúntes acerca de la omisión de socorro tienen efectos positivos en cuanto a la intervención de los mismos, aunque no existe evidencia que muestre impacto alguno en la incidencia sobre las agresiones sexuales. Los efectos en el conocimiento y las actitudes son contradictorias en todos los resultados.

    ¿Qué estudió la revisión?

    Las agresiones sexuales son un gran problema entre adolescentes y estudiantes universitarios en todo el mundo. Una estrategia prometedora para prevenir estas agresiones es la implementación de programas de prevención de agresiones sexuales para educar a transeúntes, que fomenten a los jóvenes a intervenir cuando sean testigos de este tipo de incidentes o adviertan señales de que existe algún tipo de agresión sexual. Esta revisión examina los efectos que los programas contra la omisión de socorro para transeúntes tienen en cuanto al conocimiento y las actitudes relacionadas con las agresiones sexuales, el comportamiento de los transeúntes, su intervención al momento de presenciar una agresión sexual o sus señales de advertencia, y las tasas de participación en la comisión de agresiones sexuales.

    ¿Cuál es el objetivo de esta revisión?

    Esta revisión sistemática Campbell examina los efectos de los programas de transeúntes en cuanto al conocimiento y las actitudes relacionadas con las agresiones sexuales y la intervención de transeúntes, su intervención cuando presencian una agresión sexual o sus señales de advertencia, y la comisión de agresiones sexuales. Esta revisión resume evidencia de 27 estudios de alta calidad, incluyendo 21 ensayos de control aleatorizados.

    ¿Qué estudios se incluyen?

    Esta revisión incluye estudios que evalúan los efectos de los programas de transeúntes para jóvenes en cuanto a (1) su conocimiento y las actitudes relacionadas con las agresiones sexuales, y la capacidad de intervención del transeúnte, (2) el ímpetu de los transeúntes a intervenir cuando son testigos de una agresión sexual o advierten señales de ella, y (3) la incidencia de agresiones sexuales.

    Veintisiete estudios cumplieron los criterios de inclusión. Estos estudios abarcaron el período entre 1997 y 2017 y fueron llevados a cabo principalmente en Los Estados Unidos (un estudio fue hecho en Canadá y otro en la India). Veintiún estudios fueron ensayos controlados aleatorizados y seis fueron estudios cuasi experimentales de alta calidad.

    ¿Los programas de transeúntes tienen un efecto en el conocimiento/actitudes en la intervención de peatones, o en la perpetración de un asalto sexual?

    Los programas para concientizar a los transeúntes muestran efectos en el conocimiento y las actitudes en algunos resultados.

    Los efectos más beneficiosos son que se acepte la historia contada por la víctima de la violación y los resultados en cuanto a la eficiencia de la intervención del transeúnte. También hay consecuencias diferidas (ej.: de uno a cuatro meses después de la intervención) en cuanto a asumir la responsabilidad por mediar/actuar, estar en conocimiento de estrategias de intervención y los resultados de la intención de intervenir. Existe poca o insuficiente evidencia acerca de los efectos sobre las actitudes de género, la empatía con la víctima, las actitudes de violación en citas, y en notar los efectos de las agresiones sexuales.

    Los programas de concientización de transeúntes tienen un efecto positivo en su intervención. No hay evidencia que demuestre que los programas de transeúntes afecten los índices de participación en la comisión de agresiones sexuales.

    ¿Qué significan los resultados de esta revisión?

    La ley de Eliminación de Violencia Sexual en los Campus de Estados Unidos 2013 (SaVE) procura que las instituciones educativas postsecundarias participen en el Título IX de los programas de asistencia financiera, entregando a los nuevos alumnos universitarios programas de prevención de violencia sexual, la cual incluye un componente sobre la intervención de los transeúntes.

    Los programas de concientización de transeúntes tienen un efecto significativo en su intervención. No obstante, no hay evidencia que estos programas afecten las tasas de incidencia de agresiones sexuales. Esto sugiere que los programas de transeúntes pueden ser apropiados en cuanto al comportamiento de posibles transeúntes que observen un hecho de agresión, aunque no tanto en cuanto al comportamiento de los potenciales autores del crimen.

    Los efectos positivos de los programas de transeúntes en cuanto a la intervención peatonal disminuyeron seis meses después de la intervención. De este modo, sería necesario contemplar sesiones de refuerzo para mantener los efectos de forma sostenida.

    Aún quedan preguntas importantes que requieren una exploración más profunda. Es decir, es necesario hacer más estudios que investiguen los mecanismos causales subyacentes de los efectos del programa en el comportamiento de los transeúntes (ej.: para modelar las relaciones entre los efectos de conocimiento/actitud específica y los efectos de la intervención de los peatones), e identificar los tipos de programas de transeúntes más efectivos (ej.: usar ensayos controlados aleatorizados para comparar los efectos de dos modelos de programas alternativos). Además, se necesita mayor investigación en contextos fuera de Estados Unidos para que los investigadores puedan comprender mejor el rol de los programas de transeúntes en todo el mundo.

    ¿Cuán actualizada es esta revisión?

    Los autores de la revisión buscaron estudios hasta junio de 2017. Esta revisión sistemática Campbell fue enviada en octubre de 2017, revisada en octubre de 2018 y publicada en enero de 2019.

  • Records available in English, Spanish
Factors associated with youth gang membership in low- and middle-income countries
  • Authors Angela Higginson, Kathryn Benier, Yulia Shenderovich, Laura Bedford, Lorraine Mazerolle, Joseph Murray
  • Published date 2018-11-29
  • Coordinating group(s) Crime and Justice, International Development
  • Type of document Title Protocol Review Plain language summary
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.11
Police-initiated diversion for youth to prevent future delinquent behavior
  • Authors David B. Wilson, Iain Brennan, Ajima Olaghere
  • Published date 2018-06-01
  • Coordinating group(s) Crime and Justice
  • Type of document Title Protocol Review Plain language summary
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.5
School-based interventions for reducing disciplinary school exclusion
  • Authors Sara Valdebenito, Manuel Eisner, David P. Farrington, Maria M. Ttofi, Alex Sutherland
  • Published date 2018-01-09
  • Coordinating group(s) Crime and Justice, Education
  • Type of document Title Protocol Review Plain language summary
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.1
Sexual offender treatment for reducing recidivism among convicted sex offenders
  • Authors Martin Schmucker, Friedrich Loesel
  • Published date 2017-07-31
  • Coordinating group(s) Crime and Justice
  • Type of document Protocol Review Plain language summary
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2017.8
Juvenile curfew effects on criminal behavior and victimization
  • Authors David Wilson, Charlotte Gill, Ajima Olaghere, Dave McClure
  • Published date 2016-03-23
  • Coordinating group(s) Crime and Justice
  • Type of document Title Protocol Review Plain language summary
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2016.3
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