Professor Alec Spencer hit out as Peter Duff, 28, who was convicted in August 2007 and jailed for nine years for assault, robbery and firearms offences, was being hunted by police after failing to return from home leave to Castle Huntly open prison on Wednesday.
Duff had been transferred to the prison nearly two years before his earliest parole date, had already been allowed home for Christmas and then was granted a week's home leave on Wednesday, 6 January – only just a quarter of the way into his sentence.
In a special report, Spencer had recommended that dangerous prisoners should not be sent to open prisons until the year before their earliest parole date.
Speaking out for the first time since the government's response, Spencer, former head of rehabilitation for the Scottish Prisons Service, said: "How many more times do long-term offenders need to abscond so early in their sentence before ministers realise my recommendation was a sensible solution to a serious problem? How many more Peter Duffs are we going to see?"
Last week, MacAskill said it would only "review" Spencer's crucial proposal to only allow murderers, rapists and other long-term prisoners to transfer to open prisons the year before their first parole date.
Spencer had been asked to come up with ways to reduce "absconds" from Scotland's open prisons after Brian "The Hawk" Martin went on the run from Castle Huntly in May. MacAskill announced he was adopting seven of Spencer's nine recommendations – but not his key proposal.
His comments come after a succession of high-profile escapes from Castle Huntly, near Dundee, in recent years. Ministers had taken steps to "tighten" the process of transferring prisoners after the earlier escape of Robert Foye, who raped a schoolgirl while on the run. Killer John Brown, 57, also absconded in May 2009 when he was granted a week's home leave. He fled to Gambia, in west Africa, where he was found dead in November.
Spencer said allowing long-term inmates home leave so early in their sentence only increased the chances of them going on the run, partly because more prisoners meant staff have less time to monitor them. "If they had followed my guidelines, Peter Duff wouldn't be in the open prison and, therefore, would not have been allowed home. To be sent to an open prison two years before their earliest release date really is very early."
Spencer also called on MacAskill to adopt his suggestion that prisoners in open jails be forced to wear satellite-tracked tags so that staff know where they are at all times.
Last night, Bill Aitken, Tory justice spokesman, said Spencer's comments were further proof that the SNP had "completely lost it" with regards to its policy on prisons. He added: "They must know they've got it totally wrong when Alec Spencer is forced to criticise their soft touch approach."
Richard Baker, Labour's justice spokesman, said: "We need to have confidence in open prisons and Alec Spencer's report was a real opportunity to restore that.
"It's the most damning indictment of MacAskill that he has failed to implement the report in full."
A Scottish Government spokesman said the process for transfer had been "tightened significantly" since the Foye case: "We have already seen a substantial reduction in the number of absconds from the Open Estate.
"Introducing prisoners to conditions that allow them increased freedom and more access to the community is an integral and necessary part of the reintegration and rehabilitative process.
"While we can not comment on this individual abscond, it is vital we retain these long standing arrangements which, when applied appropriately, can help reduce reoffending. The priority is returning the prisoner to custody."