Niamh Eastwood is the Executive Director of Release, the national centre of expertise on drugs and drugs law.

This morning, during an interview about London's soaring knife crime problem, David Lammy MP told BBC Radio 4's Today programme that "the police and our country has lost control of [the] drugs market". To some degree, he's right – but arguably, neither the government nor law enforcement ever had control of the drugs market in the first place, something the Home Office acknowledged in a 2017 report evaluating the national drugs strategy.

Lammy rightly said "there is no single cause" for the spike in fatal stabbings, but in denouncing the police's approach also seemed to be arguing that more drug policing would lead to a reduction in violent crime – a sentiment echoed by many on social media. The evidence, however, would suggest otherwise.

If politicians and police really want to tackle the rise in knife crime, drug policy reform is an important part of the solution. We should move away from the same old prohibitionist policies and instead focus on implementing strategies that treat drug use as a health and education issue, rather than a criminal justice matter. In recent weeks we have increasingly heard calls for an intensification of stop-and-search to tackle knife crime. However, these calls fail to properly analyse how this police power is currently used in London and how stop-and-search can contribute to young people losing trust in the police, leading them to take matters into their own hands.

Between March of 2017 and February of 2018 there were just over 128,000 stop-and-searches carried out by the Metropolitan Police. Fifty-nine percent were for drugs. The majority of these searches were of those aged 24 and under, with black people four times more likely to be targeted than white people. This is despite Her Majesty's Inspectorate of Constabulary (HMIC) reporting that black people are less likely to be caught in possession of drugs when compared to white people who have been stopped on these grounds.

This racial disparity is one of the most damning aspects of drug policing in the UK. Research has shown that our drugs laws are focused on people of colour and those who live in areas of poverty. David Lammy gets this, saying recently, "There will be a young, white, middle-class man smoking a joint with impunity at a campus university, and the police will be nowhere in sight. But a young black or Muslim man walking through Brixton or on Tottenham High Road will be stopped and searched, and end up with a criminal record that blights their life chances forever."

If the Metropolitan Police really want to tackle knife crime they should stop wasting resources on searching people for small amounts of drugs, which in most cases is cannabis. This is a view supported by DS Janet Hills, the Chair of the Metropolitan Black Police Association, who has said that the focus on drug stop-and-searches is "not worth the loss of trust or confidence with the community because of the huge violent crime problem we are working with… it's the same community that we need to give us the intelligence. It's the same community that we need as witnesses."

Drug policy reform can contribute to improved police community relations – something Portuguese police experienced when drug possession offences were decriminalised in 2001, meaning they were no longer a police priority.

Some forces in the UK also recognise the futility of pursuing low-level drug possession offences through the criminal justice system and have implemented diversion schemes which seek to educate and support people rather than criminalise them. So yes, drug policy reform can be part of the solution. However, ramping up enforcement, as suggested by Lammy, will not effectively tackle the drugs trade; the Home Office itself has said law enforcement has little impact. What it could do is lead to increased violence. It may seem counterintuitive, but when law enforcement does take down organised crime groups, it leaves an opportunity for others to take their place, often leading to "turf wars" which see an escalation in violence, not a de-escalation.

We know that drug law enforcement is targeted, disproportionately, against the black community, and is arguably a tool of social control and racial oppression. In the UK we already incarcerate a higher percentage of black men than in the United States, a fact raised by Lammy in his review of the criminal justice system. A ramped-up drug war will guarantee more young black men behind bars and will do little to abate the trade.

The lives lost in London as a result of violent crime is a tragedy. The solution, however, is not increased drug law enforcement, whether that's stop-and-search or increased enforcement against the trade. The solutions are undoubtedly complex and include increased funding for youth services, addressing inequalities in communities and supporting young people who have suffered trauma or have mental health problems. The Met could also learn from Glasgow Police's Violence Reduction Unit.