PRISON drugs policy needs to be changed with much greater focus on health concerns after nearly one third of prisoners tested positive for illegal substances as they were preparing for release last year.

Opposition politicians are calling on the Scottish Prisons Service drugs strategy to be radically reformed after 30 per cent of those “tested on liberation tested positive for illegal drugs”.

The figures come despite prisons supposedly being secure environments free from illicit substances.

Prison bosses will present the findings of the new survey to today’s Holyrood Health Committee, which is taking evidence on the Scottish Government’s drug strategy.

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SPS bosses added that a survey, which is yet to be published, found 39 per cent of prisoners reported seeing illegal drug use in prison in 2017. The same Addiction Prevalence Testing (APT), which is conducted across all Scottish prisons annually, stated that 76 per cent of inmates analysed tested positive for drugs on admission to jail.

The Scottish Conservatives justice spokesman Liam Kerr said the findings would alarm the public, who expect prisons to be secure environments, and harm the prospects of rehabilitation and reducing reoffending.

Mr Kerr said: “Prisons are supposed to be absolutely secure environments, where nothing gets in or out that isn’t supposed to. So for drug use to be so rife in Scotland’s jails is alarming.

“People understand there will always be examples where smuggled items can slip through the net. But for one in three inmates to be testing positive on release is an incredible statistic.

“There is no hope of rehabilitating prisoners while illegal substances are circulating with such ease.”

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Scottish Liberal Democrat Health spokesman Alex Cole-Hamilton has called for serious drug and sentencing reform ahead of the Health Committee meeting.

He said: “Given we know that a third of people leaving prison are addicted to drugs, it is clear that the current approach is failing. Putting vulnerable people with a history of misusing drugs behind bars won’t help them get clean.

“That is why Scottish Liberal Democrats believe we should treat drug misuse as a health issue. “If we are to really tackle drug misuse and help those most in need then we should instead be providing proper education and treatment.

“This is an approach backed up with proper medical and scientific evidence. It already works in other countries, and if the Scottish Government is willing to act it could work in Scotland too.”

More than 1,100 Scots inmates were caught taking drugs behind bars last year as figures reveal an eight-year high. Official statistics showed 1,164 inmates were caught either taking drugs or “administering them to others” last year, the equivalent of more than three a day.

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The figures – revealed in the Scottish Prison Service’s last annual report – show the number of prisoners punished over drugs last year is almost double the 634 caught four years ago.

But prison service bosses put the upsurge down to an increase in investment in tackling the problem and said the figures were positive.

A spokesman for the Scottish Prison Service said: “We take the business of people bringing drugs into prison extremely seriously.

“We have invested heavily in intelligence gathering and technology to combat the menace of drugs.

“It should come as no surprise to anyone that we are seeing more inmates caught taking drugs as a result.