Knife Crime- A review on Evidence and Policy

Introduction

This paper, first published by the Centre for Crime and Justice Studies (CCJS) in August 2006 and updated annually, reviews information on knife crime and carrying.
It assesses current programs and discusses reasons for carrying knives, aiming to reduce knife-related offences primarily in England and Wales.
High-profile knife incidents have continued to draw attention, leading to Home Office plans to improve crime recording.

The current state of the law

Knife law is complex, spread across multiple Acts from 1953 to 2006, including the
An offensive weapon is defined as “any article made or adapted for use for causing injury… or intended for such use.”
It is illegal to carry a blade or pointed article in public or schools without good reason; folding pocket knives with blades under 3 inches are exempt.
Specific Knife Controls:
- Gravity knives are defined by blade deployment using gravity.
- Replica samurai swords will be banned from April 2008 due to their involvement in serious crimes.
Violent Crime Reduction Act 2006:
- Increased maximum penalty for knife possession in public to 4 years
- Introduced measures to target specific types of knives, such as those with retractable or folding blades.
- Raised minimum age for knife purchase from ${16}$ to ${18}$ .
- Empowered head teachers and school staff to search pupils for knives.
- Lowered police search threshold in schools to “reasonable grounds for suspecting.”
- Created a new offence for using someone (especially a child) to mind a weapon.

The nature and extent of the problem (Chapter 1)

Defining “knife crime” is challenging as it encompasses various offences (e.g., possession, threat, injury), making precise measurement difficult.
Media and political reporting can be misleading due to limited clear data and misinterpretations (e.g., confusing all "knife crime" with stabbings).
Data Measures & Limitations:
- Accurate levels of knife carrying or offences are hard to determine; "definitive figures" are elusive.
- The paper relies on four official sources: British Crime Survey (BCS), police recorded crime, Offending, Crime and Justice Survey (OCJS), and Youth Justice Board–Youth Surveys (YJB–YS).
- Limitations: Many crimes are unreported/unrecorded. National statistics often can't isolate knife-specific offences. Changes in recording standards and survey methodologies affect comparability.
- The BCS undercounts due to exclusions (under 16s, homeless). Total knife-related offences could be significantly higher than BCS figures, but direct comparisons across measures are difficult.
- Despite broad estimates giving a sense of scale, precise year-by-year trends need more consistent data.

Knife carrying (the most common form of knife-related offence)

Carrying a knife, while not always leading to harm, often precedes its use in crime.
Prevalence:
- Scotland (2000): $12{\%}$ of 11–16 year olds reported carrying a sharp weapon at some point.
- YJB Youth Surveys (England and Wales):
  - 2005: $32{\%}$ of 11–16 year old pupils reported carrying a knife in the last 12 months (though comparability with earlier years is affected by wording changes).
  - 2004: Penknives were most common; flick knives and kitchen knives were also reported, with higher rates among excluded children.
- OCJS (2004 & 2005): $4{\%}$ of 10–25 year olds carried a knife in the last 12 months, predominantly males and 14–21 year olds. Most reported carrying only rarely ( $50{\%}$ once or twice).
  - Knife types: $41{\%}$ penknife, $29{\%}$ flick knife, $10{\%}$ kitchen knife (2005 OCJS).
Demographics:
- $16{\text{–}}17$ year olds are most likely to carry knives.
- Differences exist by ethnicity: penknives are more common among White pupils, while flick knives are more common among Black youth in some data.
Police data on weapon possession (including knives) showed a slight decline from 2005–06 to 2006–07, but this does not isolate knife carrying.
Summary: Knife carrying is prevalent among youth, especially late adolescents, but significant variations exist across datasets and methodologies, hindering clear trend analysis.

The use of knives in crime

Knife use in violent crime often involves threats rather than physical injury; under half of violent offences cause injury, and only ${12\%}$ of victims require medical attention.
National Estimates (BCS):
- Between 1997 and 2007, estimated knife use percentages in domestic, acquaintance, and stranger violence, as well as robbery, generally remained low and showed no strong or consistent increase.
- While upper estimates fluctuated (e.g., domestic violence ${4\%}-$ ${6\%}$ in recent years, robbery up to ${26\%}$ in some years), wide confidence intervals limit conclusions about clear trends or significant changes.
Overall: Knife use in violence has not shown consistent growth across different crime types from 1997 to 2006–2007, and variations are often within statistical confidence intervals due to small sample sizes.

Deaths caused by the use of knives

Sharp instruments are a significant method of homicide.
Homicide Data:
- Earlier Home Office analysis (1995–2000) showed about ${37.9\%}$ of homicides used a sharp instrument.
- Scotland (1981–2003): Sharp instruments accounted for around $47{\%}$ of murders.
- England and Wales (1995–2006): Total homicides rose, but the proportion caused by sharp instruments declined (from ${36.65\%}$ in 1995 to ${27.68\%}$ in 2005–2006), meaning the absolute number remained relatively stable.
- Gender: In 2005–2006, about ${31\%}$ of male and ${23\%}$ of female victims were killed by a sharp instrument.
Key Takeaway: Knives (and other sharp instruments) are a historical cause of homicide, but their share of total homicides has varied and somewhat declined, even as overall numbers of homicides increased from 1980s to late 1990s.

Chapter 2: Why carry or use a knife?

Data on motivations for knife carrying is limited, relying mostly on reports and anecdotes.
Key Motivations (YJB Youth Survey & OCJS):
- Insecurity and protection are central reasons, cited by $85{\%}$ of carriers in the 2005 OCJS.
- Victimization is strongly linked: victims are more likely to carry knives than non-victims.
- For example, $2{\%}$ of school children and $10{\%}$ of excluded children in 2004 YJB Youth Survey carried a weapon for self-defense.
Other research (e.g., "Fear and Fashion") highlights fear, victimization, and the pursuit of status through weapon possession.
Offending Link: Those who offend are more likely to carry knives, but offenders are also often victims, complicating simple interpretations.
It's important to differentiate between carrying for illegal purposes and carrying a penknife for innocent uses.
Overall: Motivations for knife carrying include protection, fear, status-seeking, and reactions to victimization, influenced by socioeconomic factors and neighborhood conditions.

Chapter 3: Who does

"knife crime

" affect most?

Age: Young people, particularly young men aged 16–24 ( $13.8{\%}$ risk), face a disproportionately higher risk of violent victimization than adults ( $3.6{\%}$ risk).
- $10{\text{–}}25$ year olds (OCJS) experienced $18{\%}$ assault victimization, highest among 10–15 year olds.
- Gender: Males are more likely to be victims of assault and homicide, with high homicide risk for young males aged 17–32.
Socioeconomic Status & Geography:
- Individuals in poorer neighborhoods, those in “hard-pressed” ACORN areas, and the unemployed experience higher rates of violent victimization.
- Homicide victims and offenders often come from lower socioeconomic groups; knife-related homicides are more prevalent in the poorest areas.
Ethnicity:
- Non-whites are less likely to be mugged than whites. Ethnic minorities are disproportionately affected by knife-related homicide (e.g., $12{\%}$ Black, $7{\%}$ Asian homicide victims by sharp instrument).
- Data on ethnicity of knife offenders/victims is limited, but some surveys show varying knife-carrying rates among different ethnic groups (e.g., White British and Black Caribbean youth in London show higher rates).
Overall: Knife crime affects young people, the poor, and certain Black and minority ethnic communities disproportionately. Causality is complex, as victims can also be offenders.

Chapter 4: Amnesties, prison sentences, education and prevention: what works for

"knife crime

Government responses include amnesties, tougher sentences, stop-and-search, and education/prevention.
National Knife Amnesty (May–June 2006):
- $89{,}864$ knives were handed in, representing an estimated very small fraction (approx. ${0.0041\%}$ ) of household knives.
- Metropolitan Police observed temporary reductions in knife offences for about 8 weeks, then levels returned to normal.
- Amnesties generally have limited long-term impact as they don't address core reasons for carrying or prevent replacement.
Stop and Search:
- A 2001–2002 Home Office report found low hit rates (7% of individuals stopped under s60 carried a weapon, with 14% of these arrested).
- The effectiveness of stop-and-search in reducing knife carrying is uncertain, and intrusive searches in schools can damage trust.
Increased Prison Sentences:
- The maximum sentence for knife possession in public rose to ${4\text{ years}}$ under the Violent Crime Reduction Act 2006.
- Evidence suggests deterrence is more about certainty of punishment than severity; longer sentences may not deter youth, who are the most common carriers.
Education and Awareness-raising:
- Programs like "Fear and Fashion" and "Be Safe Project" promote education, but rigorous evaluations proving sustained reductions are scarce.
Prevention and Broader Causes:
- The "Guns, Gangs and Knives Action Plan" includes prevention (e.g., gangs toolkit, youth centers) alongside enforcement.
- Prevention strategies are often fragmented. Addressing underlying social and economic factors (poverty, inequality, social disaffection) is crucial for lasting change, rather than just punitive measures.

Conclusion

There's a lack of a cohesive, evidence-based strategy for knife crime. Government responses have oscillated between punitive measures and prevention, but with limited proof of long-term effectiveness.
Media and political rhetoric can distort the scale of knife crime, requiring careful data interpretation.
Addressing broader social factors (poverty, exclusion, inequality) is essential for reducing knife carrying and violence.
The paper advocates for integrated research across various data sources (police, A&E, schools) to better understand knife possession and use.
Key Takeaway: Knives are instruments of violence; true prevention requires tackling the social and economic root causes, necessitating a long-term, coordinated strategy.

Notable data points and references (selected)

Knife amnesty: $89{,}864$ knives collected, showing a very small estimated impact ( ${0.0041\%}$ reduction).
Knife use in violence (BCS 1997–2006/07): Upper and lower estimates for knife use in domestic, acquaintance, stranger violence, and robbery show fluctuations, but many changes are not statistically significant due to wide confidence intervals.
Homicide and sharp instruments: Sharp instrument homicides comprised about ${28\%}$ of all homicides in 2005–2006, a decline in proportion from 1995.
Ethnicity data (homicide victims by sharp instrument): Approximately $12{\%}$ Black victims and $7{\%}$ Asian victims on average; data on offender ethnicity is limited.
Key sources: Home Office reports, MORI Youth Surveys, OCJS, "Fear and Fashion" report.