Scotland's Justice Secretary yesterday pledged to modernise a publicly owned and run prison service which houses dangerous criminals, tackles reoffending but does not lock up "flotsam and jetsam".

Kenny MacAskill outlined his vision for the future as he confirmed that a new 700-prisoner publicly-run jail will be built in the north-east to replace Peterhead and Aberdeen prisons.

Key to his vision is the setting-up of an independent commission to consider how imprisonment is currently used in Scotland. He said its remit and membership would be announced shortly but hoped it would report by next summer at the latest.

"I think there is something manifestly wrong in Scotland when, compared with 20 years ago, the number of crimes committed has fallen by 40,000 but our prison population has increased by almost one-third," he said Mr MacAskill.

"We are spending more taxpayers' money on bed and board for offenders and reoffending by those released from prison has not reduced.

"Our commitment is to a publicly owned and run prison service, more investment in replacement prisons that are fit for purpose, and a fundamental review of the role of prison.

"We are determined to develop a coherent penal policy that locks up dangerous offenders and deals with lower-risk offenders in the community but we also need to properly address the legacy of past policy and prison systems that have been good at preventing prisoners from escaping but which have leaked millions of pounds of taxpayers' money through human rights challenges.

"We are not committing to building additional prisons but we are replacing capacity no longer fit for purpose."

He said that, like the £100m replacement prison at Bishopbriggs which he announced this week would not be run by the private sector, the north-east prison would be "in the public sector, for the public good, and not for private profit".

"Rather than filling up prisons with minor offenders and building private prisons that cost the taxpayer hundreds of millions, we should ensure that prisons are used to detain dangerous criminals and punish serious offences," he added.

"A modern prison environment is needed to work with these high-risk offenders.

"Public safety must be paramount, not private profit. We want to rebuild a Scottish Prison Service as exactly that - a public service, not a management agency."

Phil Fairley, of the Scottish Prison Officers' Association, said: "We are delighted because it has lifted the uncertainty for staff at both Peterhead and Aberdeen and it secures jobs."