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Drug Testing and Synthetic Cannabis in Prisons


Drug Test Kit

Written by Professor David Nutt


Late on Saturday night, the 27th of February, I was asked to speak on the Stephen Nolan show on BBC Radio 5 about cannabis in prisons. The reason I was being interviewed was that I had supported the North Wales Police Commissioner Arfon Jones who had suggested giving prisoners cannabis to reduce other drug use and violence. 

The interview turned out to be with both Stephen and the co-host, ex-food minister Edwina Currie. It was surreal. You can listen to the interview here (2:17:15).

They could not understand, or at least refused to concede, that testing for cannabis (and subsequent elongation of prison sentences) was directly responsible for the increased use of more dangerous shorter acting and less detectable drugs such as heroin and synthetic cannabinoids (spice). And that these had led to significant numbers of deaths in prisons where cannabis had never killed anyone. And that spice use created such havoc that all prisons now require a platoon of large male paramedics to deal with the medical consequences of spice use or that over half of people in open prisons were using spice daily. And that around 5% of prison officers have now become spice “mules”. In totality a catalogue of disasters.

During the conversation, it became clear to me that nothing I could say and no evidence I could deliver would convince them that the drug testing policy, instigated over 25 years ago, was making the drug situation in prisons worse. When I asked if any data might make them consider reviewing testing policy they just changed the subject.

This is not the first time I have experienced politicians and opinion formers deny evidence, but it was the first time I had come across a complete refusal to even discuss the need to explore if policies had worked. Without such evaluation then we are on a kind of treadmill that continues to pursue failed and, as is the case with many UK and international drug policies, makes matters worse. As I argued in my recent Drug Science groundhog day lecture attempts to eliminate drug use through prohibition almost always make things worse.


But the prison situation is a special example as prisoners have almost no autonomy in terms of their life choices when in custody. Currently, they are locked in their rooms 23 hours a day, denied exercise, work and rehabilitation. Added to this the fact that so many of them have underlying mental illnesses it’s not surprising that many attempt to deaden their pain with drug and they know that cannabis is the best drug for calming their brain and helping sleep. But if the testing regime has driven out cannabis and replaced it with drugs that can kill or cause significant physical and mental harm.

What’s worse is that the prison testing scheme, which was originally set up in 1995 as a research tool to answer the question of what drug use is actually happening in prison, morphed into a powerful new rod with which to beat the prisoners back. We knew it was doomed to fail when a ten-year review of its outputs was conducted in 2005. This found cannabis was the most detected drug but after testing was initiated use of this fell, but heroin use increased. This should have warned the government that paradoxical harms of the testing policy were emerging. But the policy persisted with prisoners’ who tested positive being denied probation so increasing sentence length by in some cases several years.

The government chose to ignore this early warning sign, and, against the wishes of many prison governors, testing continued. Prison budgets also suffered from more and more sophisticated and expensive equipment needing to be purchased. I am not sure if the continuation of testing as a means of regulating drug use was thought through – it might have just carried on because no one thought to stop it or as a research tool. But its effects have been devastating with the rise of the use of shorter-acting, and hence less easily detected drugs such as heroin and pregabalin. Then spice arrived and now we have over 50 deaths each year from these products.

The effects of this epidemiology of spice have repercussions beyond the prison walls. As this report stated – the repeated demand for medical interventions had in some towns depleted community ambulance teams! In one prison, in one day 12, prisoners had to be treated for spice intoxication. Perhaps because the system is failing so badly the Department of Justice now doesn’t present data on spice.

What is particularly depressing about this situation is that we persist in a failed policy that experts have decried for decades when in other areas of health especially covid19 the full energy and wisdom of the scientific and health expert community is engaged and their solutions endorsed into immediate policy. I let the readers reflect on why that might be, but surely no one can sensibly deny the need now to move to evidence-based prison drug policies.

You can listen to the infuriating 15 minute interview here (2:17:15).

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