Scottish prisons have paid out £11m in compensation for slopping out
Millions of pounds of compensation being paid to criminals under human rights laws is "unacceptable", Scotland's justice minister has said.
So far £11m has been paid to more than 3,700 prisoners after a judge ruled their human rights had been breached by slopping out their prison cell toilets.
In England and Wales there is a one-year time bar for such claims.
Kenny MacAskill wants the UK government to legislate to bring Scotland into line with the rest of the country.
A House of Lords ruling in October 2007 said claims in Scotland could date back to 2001, when human rights laws became operational.
The anomaly has arisen because of the wording of the Scotland Act which established devolution - and included human rights provisions.
Only Westminster can change this and Scottish ministers have been urging their colleagues in London to act quickly.
Mr MacAskill told parliament £67m had been set aside for payouts to this year.
"We have already seen too much public money having to be paid out to prisoners, some of whom have committed extremely serious and appalling crimes," he said.
"We need to bring this situation to an end and the public quite rightly expects that we should do so as quickly as possible."
He said changing the law would free £50m for spending on other government priorities.
In response, Secretary of State for Scotland Jim Murphy pledged to help find a way to resolve the problem.
He said: "I do not want to see taxpayers' money being used to pay damages unnecessarily to people who have committed the most heinous of crimes.
"I will work with the Scottish Government and Ministry of Justice to find a way of resolving this complex issue which would require a change to the Scotland Act."
Labour justice spokesman Richard Baker said the issue should be pursued "constructively and collaboratively" with the Westminster Government.
"Nobody wants offenders receiving payment in this way," he said.
Robert Brown, for the Liberal Democrats, pledged his party's support but asked for details and correspondence to be made public.
Conservative justice spokesman Bill Aitken said his party was committed to dealing with the issue "as expeditiously as possible".
Slopping out was the practice of using buckets as toilets in prison cells.
Although it has now ended, claims continue to be made, dating back up to eight years.
Mr MacAskill said 3,737 cases had been settled at a cost of £11.2m.
A further 1,223 were being dealt with - an average of 200 new claims per month.