Almost half of the inmates who went on the run from two open prisons in Tayside last year were serving time for murder or attempted murder.
A total of 81 prisoners absconded from the jails in 2006
The Scottish Prison Service (SPS) has released details of past convictions of the 81 offenders who absconded from Castle Huntly and Noranside in 2006.
They included 10 killers, 29 men who had attempted to murder someone and others jailed for attempted rape.
The SPS said the issue of absconding was taken "very seriously".
Many absconders had been convicted of multiple offences, including gun crime, carrying knives, drug dealing, abduction and prison breaking.
An SPS spokesman said open prisons had a high proportion of inmates who had committed violent offences.
He said: "The purpose of open prison is to prepare prisoners, especially those who have spent some considerable time in secure custody, for release in less secure conditions.
"Those prisoners who have committed serious offences, invariably spend a long time in secure custody and are therefore most likely to benefit from the opportunities that open prisons offer."
The spokesman said measures have been put in place to assess those inmates eligible for open prison and punish those who break the rules.
He said: "Prisoners who demonstrate such behaviours risk returning to closed prisons, further time in custody and prosecution.
"There are always a minority of prisoners who will seek to undermine the aims of open prisons.
"All prisoners who access the open estate have previously undergone a rigorous risk assessment process."
Scottish Conservative justice spokesman, Bill Aitken, said: "When they built the prisons, they weren't supposed to be built with revolving doors.
"Open prisons have a use for low-risk prisoners being prepared for release, but we must never compromise public safety by putting serious, violent criminals in what have sadly become little more than holiday camps."