Mike Ewart, head of the Scottish Prison Service, said the country should look at the safety valve system of other European countries and revealed that the country is the “best” in Europe for locking up its own people.

Speaking exclusively to The Herald ahead of a major speech in Edinburgh today, Mr Ewart suggested that the global recession could also encourage people to make the right choice in

locking up less offenders.

“We are unique in Europe in having no safety valve in the prison system and prisons are committed to taking everyone sent to them by the courts,” he said. “Other European jurisdictions like Norway have no overcrowding because they have a waiting list.

“Most European jurisdictions, including Ireland, have a one in, one out system referred to as administrative release. It means releasing those in custody to be able to take new admissions.

“It would be extremely contentious to have a safety valve in Scotland but something we may have to consider. When we reached the point about a year ago of being dangerously overcrowded, then by our assessment we would have had to have considered it.

“If we had lost any accommodation through fire or any other incident, this is what we would have had to have done. When the mains water supply to Barlinnie failed, I spent sleepless nights wondering how I would decamp 1500 people.

“We would have had to have made some very rapid assessments and moved some into other establishments and moved those posing the least risk into the community on temporary release.”

Mr Ewart’s comments follow on from last year’s Prison Commission report called Scotland’s Choice. The report by former First Minister Henry McLeish presented two paths: continue as we are with ever-increasing prisoner numbers, or take positive steps to make the country safer by ending our reliance on prison as the answer to all problems.

Since then the Scottish Government has published a draft bill with a presumption against custodial sentences of six months or less and called for a greater emphasis on community sentences with an element of “payback”.

The commission pointed out that Scotland jails more and more people who are “troubled and troubling ­rather than dangerous”.

“The average daily population is 8000 to 8500, which is greater than almost all European countries, certainly central and Western jurisdictions,” said Mr Ewart.

“In comparison to most of our neighbours -- not just in Scandinavia but Ireland and France, we have significantly more national prisoners.

“Most European jurisdictions have 20% to 50% from the non-national population, in England and Wales it is about 20% but in Scotland it is just 2.8%. It is for us to claim the rather undistinguished prize of being the champion European country for locking up its own people.”

With prison costing approximately £39,000 per year for an inmate compared to approximately £1500 for a community sentence, Mr Ewart suggested that the current global recession could help change public opinion.

“Reoffending can be made worse by imprisonment and in my opinion Scotland would be safer with less people in prison and this would also be a less expensive option,” said Mr Ewart, who will speak at the 15th Conference of

Directors of Prison Administration. “Increasingly jurisdictions are going to be facing questions about the cost of prisons, against a background of reducing public expenditure. This could persuade people to make the rights choices.

“Any other service would rationalise by price or availability or use waiting lists like the NHS. For some reason if you are a bad guy you don’t have to wait.”

Scotland’s prisons should consider a controversial “one in, one out” model