Shaun Bailey, subjecting employees to random drug tests is ridiculous. It won't stop cocaine use or knife crime

I hope the London Mayor hopeful and his team rethink this ill-judged announcement

Shaun Bailey, a prospective London mayoral candidate, has called for random drug testing of all employees in companies employing more than 250 staff. His justification for this is not new: he joins Metropolitan Police commissioner Cressida Dick and previous home secretary Sajid Javid who have both tried to link middle-class cocaine use with the rise in violence and knife crime.

While there is no evidence supporting a link between cocaine use and knife crime, there is a link between drug use and class. Namely the political class can use drugs like cocaine without facing consequences, unlike those from lower socio economic groups and particularly anyone who is not white. Several high-profile politicians have confessed or been outed over their drug use and not one has been penalised.

Contrast this with the disproportionate number of young black men who are stopped and searched on the basis of profiling.

Bailey’s pledge to introduce workplace drug testing does nothing for his credibility. He knows, or should know, there is no evidence to support this policy. As with legal markets, the drug market is diverse: those dealing and using cocaine are not the same as those using and dealing crack cocaine and heroin. The latter is associated with violence whereas the former is not. So if the justification for invading employees' privacy is to make a dent in knife crime, all the evidence suggests it will be a failure.

But I suspect that isn’t the point of this announcement. It's a blatant attempt to capitalise on people’s fears and win their votes.

What Bailey seems unaware of is that the people he is targeting are his voters and they are not a minority group. Cocaine use has been rising across the UK in recent years, as the drug has become more affordable and quality has improved. While some people will develop a problem, the vast majority won’t. It would be far better to spend time thinking about how those who are at risk could be helped and supported rather than elaborately caught out.

It is not just employees who Bailey is leaning on but employers will be named and shamed too. He plans to publish the names of companies where positive tests are returned. It's difficult to imagine a more coercive and uncaring approach to this issue. It is not only evidence-free but morally cruel.

Drug testing employees may sound like a fool-proof scientific activity, but unfortunately, it's not. Unlike elite athletes the standard of drug testing that is likely to be used by employers will be less than perfect. Most employers won’t want to invest the time and money in the elaborate and legally robust system that top athletes are subject to. Instead this will be testing on the cheap with results to match. Unlike cannabis, cocaine metabolises within hours, not weeks, so there is a very short window of detection. This raises the prospect of tests being carried out on individuals who have used cocaine but it's left their system by the time the test is carried out. This will give false reassurance to employers and do little to help employees.

Apart from the science and evidence being problematic, it is doubtful that some employers will be willing to participate in such a scheme. Some will rightly view it as invading their employees' privacy but some will be all too aware of why their employees are using drugs like cocaine, which can enhance energy and performance in the short term at least.

I hope Bailey and his team rethink this announcement. They are in a position to make a difference on the issue of drugs – not by marginalising and blaming people, but by providing leadership. Voters will respond to policies that aim to help those in need, providing the case is made clearly and based on the facts.

If this pandemic has taught us anything, most people want to do the right thing, and they will listen to experts and comply with measures that ensure we are all safer. Every aspect of Shaun Bailey’s announcement runs counter to this.

Ian Hamilton is associate professor of addiction at the University of York.