Data Driven Policing: Homicide Concentration and Distribution Patterns in London

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Data Driven PolicingHomicide Concentration and
Distribution Patterns in London
Detective Superintendent Mark Jackson Barak
Ariel, PhD
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All Homicide Offences (1st Apr 00 to 31st Mar 10)
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Research Questions?

• Is Homicide a random event in time?
• Is Homicide a random event in space?
• What are the possible links between homicide
  locations, offenders, victims and other factors,
  at the micro-place level?

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Place-Based Criminology

• The stability of crime trends at places over
  time suggests a strong coupling of crime to
  place
• David Weisburd, Cody W. Telep, Anthony A. Braga
  (2010). The Importance of Place in Policing
  Empirical Evidence and Policy Recommendations.
  Bra Publications

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(some of the) Research Evidence

• 74 of serious gun crime assault was committed in
  5 of street and intersections
• (Braga et al 2010)
• 5 of addresses/intersections produce 100 of the
  calls for predatory crimes, i.e. robbery
• (Sherman et al 1989)
• 3.5 of addresses account for 50 of crime calls
• (Sherman et al 1987)

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London Metropolitan Police Data

• 10 year period from (1.4.2000 - 31.3.2010) within
  the Metropolitan Police area of London
• Homicide Locations 1,664 (98.2 geo-coded)
• Victims Locations 1,714 (87.3 geo-coded)
• Offenders Location 2,382 (84.3 geo-coded)
• Socioeconomic Deprivation Measures for 4,760 LSOAs

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Temporal Patterns
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London Homicides (2000-2010) by Year (n1,714)
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London Homicides (2000-2010) by Month (n1,664)
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London Homicides (2000-2010) by Day of Week
(n1,664)
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London Homicides (2000-2010) by Hour of Day
(n1,664)
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Spatial Patterns
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Homicide Offence locations by Borough
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Homicide Offence locations by Ward
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Homicide Offence locations by LSOA
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Or put it another way
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Zero Homicides (1st Apr 00 to 31st Mar 10)
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Homicide Offence locations in Westminster Wards
West End
St James
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All Domestic Violence Homicides (1.4.00 to
31.3.10)
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All Gun-Related Homicides (1.4.2000 to 31.3.2010)
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All Knife-Related Homicides (1.4.2000 to
31.3.2010)
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Connecting Homicide Places to Peopleat LSOA
level
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Homicide Offenders

• 72 of London's LSOAs (n3,414) did not have a
  resident accused of homicide

Homicide Victims

• 75.5 (n3,597) of LSOAs did not have a resident
  victim of homicide

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Concentrations of Homicide

• 6 of LSOAs contributed 42 of homicides over 10
  year period

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Concentrations of Offenders

• 9 of LSOAs contributed 53 of homicide offenders
  over 10 year period

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Concentrations of Victims

• 5 of LSOAs contributed 35 of homicide victims
  over 10 year period

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Deprivation Levels at LSOA
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Summary 1

• There are predictable hot times of homicide
• The stability of homicide trends at places over
  time suggests a strong coupling of
• Homicides to place (6 ? 42)
• Homicide offenders to place (9 ? 53)
• Homicide victims to place (5 ? 35)

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Summary 2

• 2 of homicide offenders kill within their LSOA
• 60 of victims are killed within their LSOA
• Medium-size relationship between overall crime
  patterns deprivation levels with
• Homicide LSOA (ES 0.5)
• Homicide victims LSOA (ES 0.5)
• Small but negative relationship between overall
  crime patterns deprivation levels with
• Homicide offenders (ES -0.14)

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Data Driven PolicingHomicide Concentration and
Distribution Patterns in London
Detective Superintendent Mark Jackson Barak
Ariel, PhD