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Knife crime has become a prominent and seemingly intractable problem in England & Wales. Theory and evidence indicate that reducing crime opportunities is an effective means of crime control, including restrictions on lethal weapons. While public debate has centred on zombie ...
Knife crime has become a prominent and seemingly intractable problem in England & Wales. Theory and evidence indicate that reducing crime opportunities is an effective means of crime control, including restrictions on lethal weapons. While public debate has centred on zombie and other ‘status’ knives, the most prevalent homicide weapon is a kitchen knife. Here we argue that replacing lethal pointed-tip kitchen knives with round-tip knives would reduce knife crime with little or no displacement, and may reduce other forms of violence. Drawing on the approach to remove fossil-fuel vehicles from roads, we propose a phased removal of lethal kitchen knives and estimate this will cut knife crime in half.
Updated 30 October 2024
On Monday 29 July 2024, BBC news reported that:
“Three young girls have been killed in a "ferocious" knife attack in Southport at a Taylor Swift-themed dance and yoga event…. Eight more children were injured, with five left in a critical condition, after the incident late on Monday morning. Two adults also suffered critical injuries, Merseyside Police said.
Armed officers detained a male and seized a knife, with police later saying that a 17year-old boy had been arrested on suspicion of murder and attempted murder. The attack is not being treated as terror-related, police said.” (Culley and Khalil 2024).
This tragedy furthered mounting perception that knife crime in England & Wales was out of control. In the year ending March 2023 there were close to 50,000 knife crimes recorded by police, and knives were the most popular weapon used in homicide (reviewed further below with other evidence). Faced with a series of high-profile incidents, the government sought to strengthen existing restrictions on carrying zombie knives and machetes with a proposal to ban sales (Nevett 2024). This complements policy and practice to reduce knife crime including police operations and legal measures such as the 2019 Offensive Weapons Act.
Policy and practice to address knife crime in England and Wales is reviewed elsewhere (Bullock et al. 2023, Sidebottom et al. 2021), and we give only a brief recap here. The 2019 Offensive Weapons Act made it illegal to possess dangerous weapons in private rather than solely in public as previously. It introduced Knife Crime Prevention Orders which are court orders that require an individual to desist from activities that might involve violence. The 2019 Act also made it illegal to carry a kitchen knife without good reason, setting a legislative precedent and reference point for what follows.
Major recent police operations have targeted knife crime (Bullock et al. 2023), and a review assessed eight types of police response (Sidebottom et al. 2021). The four responses aiming to reduce knife crime were: school-based interventions, police stop and search, focused deterrence, and import enforcement. The four responses aiming to reduce knife carrying were: knife sweeps, knife bins, knife arches (metal detectors), and ‘teachable moments’ (Sidebottom et al. 2021). The study concluded that relatively little is known about what works. While there is extensive support among police for knife-crime interventions, effective problem-solving efforts have proved difficult to develop (Bullock et al. 2023).
A public health approach underpins the introduction of Violence Reduction Units (VRUs) in the 18 police force areas with the highest rates of hospital admissions for knife crime injuries (Home Office 2022, 2024). The VRUs promote multi-agency approaches, data sharing, seek to engage young people, and commission evidence-based interventions. To date there has been limited evaluation and it has not been possible to attribute change in knife crime to VRU activities.
Efforts have been made to reduce the availability of status knives. A voluntary agreement with major retailers has been in place since 2016 and was extended in 2024 (Home Office 2024). This has sought to restrict in-person and online sales of dangerous knives to customers aged under 18 using age verification checks similar to those for alcohol sales. The think 21’ or ‘think 25’ approach encourages retailers to ask for proof of age from customers who may be under-age, implemented via staff training. Retailers are also required to ensure that knives are securely displayed and packaged to minimise risk including theft. Some online retailers including eBay restrict the sale of all knives except cutlery. Others such as Amazon require age verification on delivery (Home Office 2024), though the present authors are unclear on whether or how this is enforced.
Overall, then, the repertoire of policy and practice known to be effective against knife crime is limited. Here we suggest a change of emphasis. The theoretical and evidential platform for the study is outlined first. It shows that reducing crime opportunities is an effective means of reducing crime, including control of lethal weaponry. We then examine evidence that the most popular homicide weapon is a knife, and that – contrary to the orientation of much of the public debate – the most prevalent knife in homicide is a lethal pointed-tip kitchen knife. We follow this with research evidence that, perhaps not surprisingly, pointed-tip knives are more harmful than round-tip knives. This is the foundation for our proposal to phase-out lethal pointed-tip knives, particularly kitchen knives, for which round-tip knives can be substituted. We address the potential criticism that crime will displace to other weapons and explain why it is unlikely to occur to any great extent. The schedule we propose draws on that for fossil-fuelled vehicles, involving consultation plus periods to allow knife manufacturers and customers to adapt.
We define knife crime as any crime involving a knife or sharp instrument, consistent with the Office for National Statistics and a recent House of Commons briefing (Allen et al. 2023). This includes assaults and threats with knives plus other crimes where a knife or sharp was instrument was involved which could include theft and robbery, sexual assaults, and other crimes. Pointed-tip and round-tip knives are sometimes referred to here as lethal and non- lethal knives respectively because these terms more accurately reflect the problem under discussion.1
This study is framed in terms of a crime opportunity perspective. A crime opportunity is any situation in which the perceived benefits of committing a crime outweigh the perceived costs. Decisions are subjective and context-dependant, which means there are situations where one person perceives a crime opportunity where another does not. Hence whether a kitchen knife is viewed as a weapon depends on its availability, the context (Sunday lunch or an alcohol-fuelled Saturday night argument), and the individual (their capabilities, experiences and so on).
The central theoretical elements of the perspective are routine activities, rational choice and situational crime prevention (Cohen & Felson 1979, Clarke & Cornish 1985, Clarke 2018). crime occurs when a potential offender and suitable target converge when there is no capable guardianships. Offenders make decisions that pursue a goal, based on their existing knowledge, experience and information. This means that poorly-informed, poorly-made and other seemingly ‘irrational’ decisions are made within the same cost-benefit framework. When it comes to crime, key decisions relate to initial involvement in crime (often by adolescents), decisions to continue committing crime (which can lead to habitual offending), and desistence. For example, few young people carry weapons before they have become involved in crime, and weapon-carrying increases with habituation. Individual criminal events comprise decision sequences known as scripts (Cornish 1994, Dehghanniri & Borrion 2021, Leclerc 2016). A knife crime script for a domestic assault may involve a history of other forms of violence, an immediate precursor argument, location of the argument at home and in the kitchen, a physical fight, and the aftermath of escape and/or dealing with injuries. A script for crime where knife-carrying is central may involve decisions relating to knife acquisition (purchasing or stealing a knife), decisions relating to when and where to carry, concealment decisions, and then a series of decisions relating to each crime in which the knife is involved (each involving preparation, target acquisition, commission and aftermath decisions). Scripts have become increasingly prominent in crime prevention research because each decision identifies a potential pinch-point for intervention.
Situational crime prevention aims to reduce or block crime opportunities to reduce crime or its harms. Reducing crime opportunities shifts offenders’ decisions, at any point in the script, away from crime. If, say, the kitchen does not contain lethal knives, there is no opportunity to decide to use a knife. If lethal knives are difficult to obtain then decisions to carry become more difficult. Knife crime prevention efforts can work by different situational crime prevention mechanisms which may include controlling access to weapons, removing knives that facilitate crime or reducing temptation to commit a crime, and we return to prevention efforts later.
More generally, there are many documented examples of different types of property and violent crime prevented by situational crime prevention efforts, some of which are listed in Table 1.
Table 1: Examples of successful situational crime prevention projects
Responsible drinking practices in Australia |
Street closures to prevent drive-by shootings in Los Angeles |
Video cameras in housing for retired persons |
Anti-cloning measures for U.S. cell phones |
Alley gates to reduce burglaries in Liverpool |
Airline baggage and passenger screening |
Cash reduction in U.S. convenience stores |
Anti-robbery screens in London post offices |
Automated checking of income by applicants for housing subsidies in Sweden |
Systematic cleaning of graffiti on New York City subway cars |
Electronic and ink tag on merchandise in U.S. clothing stores |
Speed cameras and random breath tests in Australia |
Exact change and drop safes on U.S. buses to prevent robbery of bus drivers |
Safes with time locks to prevent betting shop robberies in Australia |
Removal of gas and electric coin meters from council houses in England to prevent burglary |
Source: Clarke (2018).
The specificity of the examples in Table 1 captures the nature of many crime and context- dependent situational crime prevention efforts. Different interventions are typically needed for different crime types in different contexts. The property and violent crimes addressed by situational prevention efforts includes cybercrimes (Ho et al. 2022).
The flagship example of effective situational interventions is the international crime drop. In recent decades, security improvements have reduced many types of crime. Vehicle security improvements, particularly the vehicle engine immobiliser, have not only largely eliminated joyriding and other temporary theft but have also significantly reduced professional and organised car theft (which now requires planning, specialist skill and equipment plus reliable contacts for vehicle disposal). Household burglary has been reduced by gradual and seemingly mundane improvements to the quality and quantity of door and window security fixtures and fittings. As a result of these high-volume crimes being reduced, young offenders were less involved in crime with fewer graduating to violent crime. In England & Wales, car theft, burglary and violence fell by close to 90 percent between the early to mid-1990s and 2023 (Figure 1).
Figure 1: The crime drop in England and Wales by 2023 (Source: CSEW; ONS (2024a). Violence, domestic burglary and vehicle-related theft incidence rates each indexed to its peak year)
Guns are more deadly than knives, and gun control fits with the situational crime prevention framework. England & Wales has significant gun control compared to the United States. The rate of gun-related homicide in the US is over 40 times that of the UK for all gun homicides, and over 50 times for handguns (Table 2). While the non-gun US homicide rate is also higher, it is fractionally so in comparison, and may reflect the normalisation of violence enshrined in US gun control laws.
Table 2: Comparison of gun and non-gun homicides in England and Wales and in the United States 2009-2013
|
Number of homicides | Annual rate (per 1 million population) |
Ratio | ||
Type of murder | England & Wales | United States | England & Wales | United States | England & Wales: United States |
All gun | 205 | 50190 | 0.73 | 32.22 | 1: 44.0 |
Handgun | 118 | 35362 | 0.42 | 22.70 | 1: 53.9 |
Non-gun | 2584 | 23644 | 9.64 | 15.19 | 1: 1.6 |
Total | 2907 | 73834 | 10.37 | 47.41 | 1: 4.6 |
(Source: Clarke 2018 based on data from Home Office and Office for National Statistics for England and Wales, and Federal Bureau of Investigation for United States).
A common criticism of efforts to reduce crime opportunities is that offenders displace to commit the same crime by other means. However, extensive research shows that prevented crime typically does not displace, or may do so to a limited extent in the aggregate (Guerette & Bowers 2009). In the context of knife crime, if the availability of a particular type of dangerous knife is reduced then the potential criticism is that offenders will use a different type of knife or another weapon. We return to this later.
The most reliable source of information on the extent and trends for many crime types is the Crime Survey for England and Wales. This is a methodologically rigorous survey that asks a sample of around 30,000 people annually about their experiences of crime. However, knife crime is fortunately rare, such that the CSEW is unable to produce statistically reliable trends. While this indicates the comparatively low prevalence of knife crime, it requires other sources to identify trends.
Three sources from which trends in knife crime can be derived are police recorded crimes, hospital records, and homicide data. Each has their strengths and weaknesses. Not all knife crime is reported to or recorded by the police. Only some of the more serious offences will result in a hospital admission linked to a knife crime. Homicides comprise a small part of the overall picture of knife crime, albeit by far the most serious.
The main trend in knife crime indicated by each of these sources is similar. From a relative low in 2012-13, knife crime increased through the 2010s to peak between 2017 and 2019 and has since been mostly in decline (Figure 1). One source speculated that the increase reflected growth in the global cocaine market and violence relating to county lines distribution networks (Davies & Farrell 2024). The similarity in the trends from the different sources adds credibility, suggesting the trends may broadly represent what has happened. There were around 50,000 knife crime offences recorded by police in the financial year 2022/3, and, of the three measures, recorded crimes evidenced the largest proportional increase over the last decade.
Figure 2: Knife crime trends for three indicators
The number of knife crimes began to decline before the covid-19 pandemic. The decline was more pronounced during the pandemic, with evidence of a resurgence in 2022 as restrictions were removed, consistent with trends in many other crime types (Seyidoglu et al. 2024). Two of the three indicators show a decline for the most recent year of 2022/3 compared to the preceding year (Figure 1). The most prevalent crime types involving knives are assaults2 and robberies which drive the overall trend, though threats with knives also increased and did not decrease during the pandemic to the same extent as knife-related theft and robbery.
Figure 3: Crime types involving knives. (Source: ONS 2024b).
Knives or sharp instruments have long been the most prevalent means of committing homicide in England and Wales (Figure 4). This suggests knives would be an appropriate strategic national priority for homicide prevention efforts.3 The increase in knife-related homicides in the 2010s, along with the broad category of ‘all other methods’ accounted for the bulk of the increase in homicides over that decade. Note that the 89 asphyxiated victims of the Hillsborough disaster were included in the 2016-17 homicide statistics and account for the anomalous increase in ‘strangulation or asphyxiation’.
Figure 4: Means of homicide in England and Wales (Source: ONS 20244)
Since 2022 the Office for National Statistics has made available information on the type of knife used in homicides. The type of knife used was known and recorded for the majority of knife-related homicides (192 of 233). For homicides where the type of knife used was known, by far the most prevalent was kitchen knives (Figure 5), the next most prevalent being ‘other knife’ which does not fall into any of the remaining categories. While zombie and hunting knives appear to dominate much of the public discussion, they each account for between two and four percent of knife-related homicides. The eight non-other categories (zombie, hunting, combat/Rambo/military style, flick and lock knives, machetes, swords and axes) are combined, they account for a quarter of knife-related homicides.
Figure 5: Type of knife or sharp instrument used in homicide in England & Wales 2022-23 (Source: ONS 2024b; homicides where type of knife used is known)
Kitchen knives are more available in domestic settings. Where the nature of the relationship is known, in around three quarters of murders of women the suspect was a partner, ex-partner or other family member, compared to around 20 percent for males (Figure 6). Of these female homicides, most were partners or ex-partners. This suggests that, if kitchen knives can be made less lethal it will disproportionately reduce murder of women and girls.
Figure 6: Percentage of homicides where suspect known to victim, by sex of victim, where relationship is known (Source: ONS 2024b)
Knives with points, whether straight-edge or serrated, have been shown to result in far more damage than knives with blunt tips. The effects upon humans were mimicked through testing the knives against different materials in pioneering work by Nichols-Drew and colleagues which is summarised in this section (Nichols-Drew 2019, Nichols-drew et al. 2020, Nichols-Drew 2023).
Five different types of knives were tested. It may seem unsurprising that the study found pointy knives to be by far the most damaging, but this is what evidence-based research is about. Without such basic evidence, critics would say that there is no proof that pointed-tip knives are the problem.
In a policy brief, Nichols-Drew (2023) makes three recommendations. These are the promotion of the use of rounded knives as safe alternatives to hazardous pointed knives, that governments should legislate to that end, and that there is engagement with knife manufacturers and retailers to create and supply rounded knives (Nichols-Drew 2023; 3). The present study locates these proposals in the context of theory, evidence and existing policy relating to crime prevention and knife-crime prevention, and in proposing a practical approach to policy adoption in a realistic timeframe.
Petroski’s historical study of the evolution of everyday things notes that
“… In 1669, as a measure to reduce violence, King Louis XIV [of France] made pointed knives illegal, whether at the table or on the street. Such actions, coupled with the growing widespread use of forks, gave the table knife its now familiar blunt-tipped blade…. Whereas …. kitchen knives have changed little over the centuries. Their blades have remained pointed.” (Petroski 1994; 12-14)
Elsewhere it is argued that many crime prevention efforts are such a mundane part of everyday life that they are easy to overlook and sometimes taken for granted (Farrell & Tilley 2021). We suggest this is true in relation to table knives. Think about the last knife you used a knife in a café, restaurant, or in your dining room. Dining knives usually have a rounded end. Why? The reason is that they are used frequently by everyone and would pose a major threat of violence if they were pointed. These are the majority of knives in everyday use, including by children, and account for the majority of knife usage. Yet the rounded end means they are not viable weapons. While there are still a few pointed ‘steak’ knives they are, for the most part, specially distributed when needed. Recognising that round-tip knives are an almost universally used crime prevention tactic, and that there is an implied consensus on their importance for public safety and crime prevention, brings us to the proposal.
Recent policy developments relating to motor vehicles evidence the viability of the proposal outlined here to control knife crime. Only a few years ago, many readers would have scoffed at the suggestion that society could phase-out the internal combustion engine. It was largely unthinkable to tamper with an iconic, economically important, and integral component of everyday life. At the time of writing, increasing numbers of countries are phasing-out fossil-fuelled vehicles in favour of electronic vehicles, active travel, and public transportation (BBC 2020, International Energy Authority 2020). In the UK, sales of petrol and diesel engines will end by 2030, and all new cars and vans will have zero emissions by 2035 (Department for Transport 2020). This schedule gives manufacturers and consumers time to adapt.
The policy adopted for fossil-fuelled vehicles provides the model for our proposal relating to knife-crime. Indeed, our proposal is modest in comparison. Drawing on this evidence, we propose an incremental phasing-out of pointed knives and an incremental phasing-in of round-tip knives for all culinary, domestic and other purposes (Table 3).
Table 3: Phasing-out knife crime
Phase | Year | Activity |
1. | 2026-2030 | Manufacturers develop safe knives for culinary and other uses. Marketing campaigns to promote knowledge, purchase and use of safe knives. Start of ‘natural wastage’ process: old discarded knives replaced with similar non-lethal version. Consultation and consideration of exemptions. |
2 | 2031-2035 | Depletion of stocks/sales of lethal knives; increased stock/sales of non-lethal knives. Subsidised grinding of remaining lethal knives to round the tips. |
3 | 2036-2040 | Only safe knives on sale. Incentivised removal of dangerous knives from homes and workplaces. |
4 | 2041 onwards | Ban on manufacturer, sale, possession and use of dangerous knives. |
The process is here envisaged as having four stages across two decades. This preliminary proposal should be refined in consultation with interested parties. The phased approach is intended to allow markets and manufacturers time to adapt. It will take time to introduce non-lethal knife designs into production processes and to deplete the manufacture of lethal knives. It will take time to exhaust existing stocks. For the most part, the process of replacement will occur as natural wastage, that is, as old knives are discarded and replaced with a similar less-lethal alternative.
Enterprising manufacturers should quickly the opportunity that this proposal represents. Policy development might consider whether any aspects need to be subsidised or incentivised. It may be that kitchen knife purchases represent a sufficient small proportion of disposable income that subsidies are not required in most circumstances. Consideration should be given to subsidised grinding of existing knives so that businesses can keep knives where there has been significant investment, and so that individuals can keep treasured knife sets. Consideration may need be given to certified exemptions that exceed a requirement threshold and justify ownership of a lethal weapon.
International trade agreements will need to be reconciled as standards change in England & Wales. There are likely to be few professions where a lethal knife is required to complete a task, and these should be considered on a case-by-case basis. Policy change is probably best framed as improvement to health and safety measures, similar to those for a wide range of products where safety standards have been introduced to reduce risk to life and limb. These things take time.
The specifics of the schedule shown in Table 3 can be refined as required. The primary notion is that of shaping behaviour gradually while allowing time for changes to take place without significant disruption to markets.
Round-tip kitchen knives are already on the market. The Offensive Weapons Act 2019, which classified kitchen knives as an offensive weapon, is cited by one manufacturer as prompting their work on ‘safety first’ kitchen knives (Figure 7). The manufacturer reports “a new generation of kitchen knife that has safety front of mind, yet still answers everyday food preparation needs.” (Viners 2019). The knife set was developed in consultation with 1700 consumers “who shared their thoughts on the functionality and aesthetics” of knife designs “eliminating the tip of the knife to make it safer to use without compromising on performance.” (Viners 2019).
Figure 7: A set of safe kitchen knives (Source: Viners5)
The issue of displacement was touched on earlier. Both theory and evidence indicate that when crime is prevented, displacement often does not occur or may occur to a limited extent. Nevertheless, we anticipate that displacement will be raised as a criticism of the present proposal. This section focuses on the possibility of displacement if lethal kitchen knives were controlled, particularly the possibility of a tactical switch to another sharp instrument or other weapon.
Much knife crime relates to knife carrying. We suggest the carrying of other weapons is less likely overall if pointed knives are removed from the equation. ‘Status knife’ is the term capturing how a key issue is the psychological reward from peers of carrying some types of knife: the carrier may derive some kudos from peers and be able to threaten others. Kitchen knives may have lower status than zombie knives, but for present purposes let us assume that being armed brings status. Once pointed-end knives are removed, what other weapon might be a good substitute? Perhaps a chain of some sort could be carried as a weapon, except it is less readily available, harder to wield as a weapon, and less injurious on average. The status for chain-carrying is likely to be less than that knife-carrying, which means the temptation to carry would also be reduced. Most other objects are inferior both in terms of status and when used as weapons.
What about ‘tinder-box’ violence occurring in the home? If lethal kitchen knives are not available, what is the next-best alternative? Perhaps scissors or screwdrivers? Many scissors are already rounded rather than pointed. Further, the design of scissors makes them unwieldy for the purpose of stabbing. The default use of scissors involves the fingers being threaded through handles, which makes using them to threaten or stab offers an uncomfortable grasp. To use the term favoured by designers such as Donald Norman (2002), scissors do not readily afford the act of stabbing. Scissors are also less numerous than kitchen knives and less likely to be on open display (compared to, say, a box set of knives). The reason that scissors do not already feature more prominently in the crime statistics for sharp instruments is that they are a significantly inferior weapon.
Another contender is a screwdriver. However, screwdrivers also do not comprise a large component of existing knife crime statistics for a reason: they are not as readily to hand as knives in a kitchen or other domestic setting, aside from perhaps a toolshed or garage. They are significantly inferior as ‘status’ weapons, arguably indicating the inability of the carrier to find a ‘proper’ status weapon, that is, a pointed knife.
Glass bottles are a potential alternative. However, most bottles and other domestic containers these days are plastic, cardboard or aluminium. Those glass bottles which hare prevalent are often unsuitable – they are the wrong size or too fragile, for instance. A perfume bottle makes a poor weapon. Some beers bottles are too large (one litre bottles), and others too small (stubby 330ml bottles), while aluminium cans contain much of the beer for domestic use. The popularity of recycling means empties are routinely disposed of, reducing accessibility. Use of a bottle as a weapon also requires a user to recognise the potential of a bottle as a weapon which cannot be assumed, as well as finding one. Further, operationalising a bottle as a weapon requires skill to avoid completely shattering the bottle which can injure the holder.
It is not obvious if other kitchen items will serve. Most require more effort or skill to utilise in a lethal fashion. Whisks and spatulas are absurdly inappropriate. What about other household items? Perhaps a pencil could be a lethal stabbing weapon, but it is structurally weaker and likely to do far less damage than a pointed kitchen knife. Some garden tools – secateurs and such – are potentially dangerous but on average require significantly more time and effort to retrieve from the shed, garage or elsewhere, providing cooling-off and escape time. Generally speaking, garden-tool weapons are a poor and unlikely substitute.
What about blunt objects and other potential weapons? Heavy ornaments or rocks from the garden are potential weapons but take time and effort to acquire and are wielded with difficulty. Books and remote controls may be available but are insufficiently dangerous for the most part. For most other items their consideration quickly lapses into the ridiculous.
Put another way, the reason that the crime category used here is defined as ‘knives and other sharp instruments’ is because knives are significantly more dangerous than the closest substitute, and all alternatives are inferior - they do not afford threats or stabbing to the same extent - and are less readily available.
This discussion is consistent with the existing theory and evidence relating to crime displacement. Displacement is generally scarce. It may occur in some instances but in the aggregate there is a significant net reduction in crime. The evidence for the fact that other items are inferior is the fact that they are not already the first choice: lethal kitchen knives are the weapon of choice for homicide in England and Wales for a reason. We conclude that some small amount of displacement may occur but that for most part it will be conspicuous by its absence: look again at the difference in gun-related deaths in the UK and the US detailed earlier.
A ‘diffusion of benefits’ effect is framed as the opposite of displacement (Guerette & Bowers 2009). Numerous evaluations have found that crime prevention effects extend beyond the initial scope, or that an anticipatory benefit is induced before a policy is implemented (Smith et al. 2022). We suggest that both types of diffusion may occur here. If customers and manufacturers anticipate legislative change, then behaviour relating to lethal knives may change in advance. Similarly, an impending ban on pointed knives may cause a broader effect upon violence and other types of crime. We would not only expect a reduction in homicides but also other knife-related crime types, proportional to the use of kitchen knives (which, in the context of bans on other lethal knives will be more effective overall). Previous research suggests that reducing crime opportunities for young people reduces their involvement in crime, which in turn reduces the size of cohorts progressing to habitual involvement in crime (Dixon and Farrell 2020): we cannot rule out this type of broader beneficial effect if the murder weapon of choice is eliminated.
In this context, lethal pointed knives are also a cause of many avoidable injuries in kitchens and elsewhere. Knive-related injuries account for over 10% of major injuries reported to the government’s Health and Safety Executive (HSE) and 58% of all work-related accidents involving manual tools (British Safe Industry Federation 2021). The HSE report the following example
“While trying to open a 25 kilo bag of potatoes, the commis chef sliced the corner of the bag using a 12-inch fish filleting knife. With the knife still in his right hand pointing upwards, he then attempted to move the bag. The cut section of bag gave way causing the knife to be thrust upwards into his face, causing a severe laceration.” (at https://www.hse.gov.uk/catering/knives.htm)
A significant beneficial diffusionary aspect of safe knives would be reduced injurious ‘accidents’ in restaurants, in homes and elsewhere, in addition to reducing knife crime.
Knife crime is a significant problem. It has been a dominant feature of news media and political discussions about crime in England and Wales in recent years, and knives are the most prevalent murder weapon. Existing efforts to reduce knife crime have met with limited success and have often focused on zombie knives, machetes and other status knives. In that context this study is ambitious in proposing a significant policy change and schedule to reduce knife crime. It details the mechanisms by which knife crime will be reduced with little or no displacement, and suggests other forms of crime and criminality may also decline as a positive knock-on effect (a diffusion of preventive benefits). While the focus is England & Wales, there are significant implications for other countries which, depending on the nature of their knife crime problem, may wish to consider adopting this approach.
Central to the study is an original proposal. It is novel in the emphasis upon lethal knives in everyday life which contrasts with most media and policy debate centred on zombie and other ‘status’ knives or on gangs and young people. To do this, the study was underpinned by evidence of the dominant role of kitchen knives in homicide, in the context of extensive theory and evidence on the effectiveness of reducing crime opportunities. Few readers, we suggest, will have previously recognised the important crime prevention role of rounded-end dining room knives.
The proposal outlined here will affect the lives of most householders and some businesses in England and Wales. Extensive justification such a policy change is required. But the study is rigorous in being evidence-based while informed by proven theory. Further, we detail the mechanisms by which the policy would work, explain why little or no displacement is expected and why, in contrast, a diffusion of benefits is likely.
Kitchen knives are the murder weapon of choice in England and Wales. The sharp tip of kitchen knives is unnecessary for culinary purposes: it is possible to julienne a carrot, or even chop a butternut squash, without a lethal weapon. Safe kitchen knife designs already exist and are in production, and safe knives are the default in dining rooms to the extent that we barely notice their crime prevention role. Extensive theory and evidence support the proposal, while fossil-fuel motor vehicles offer a high-profile precedent using a phased approach. The proposal will, we suggest, reduce homicide by half in England and Wales, reduce other crimes in proportion to the use of lethal kitchen knives, potentially reduce other crime types and criminality as a by-product, and reduce non-criminal knife-related injuries.
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