A prisoner was awarded compensation by a judge

The decision, made in the Court of Session in April, could cost the Scottish Executive millions of pounds in compensation.

More than �2,000 was awarded to a prisoner in Barlinnie who had claimed the practice of slopping out was degrading.

The ruling paved the way for a series of similar claims from other inmates.

The court awarded armed robber Robert Napier more than �2,000 in compensation.

'Administrative error'

Justice Minister Cathy Jamieson insisted at the time there were grounds to challenge Lord's Bonomy's judgement.

She argued there were legal issues that needed to be clarified.

But in order to do that an appeal had to be lodged at the Court of Session within 21 days.

An "administrative error" is being blamed for ministers' failure to meet the deadline.

The SNP's justice spokeswoman, Nicola Sturgeon, said: "It is quite unbelievable that after losing the slopping out case in the first place, the Scottish Executive has failed to hand in the correct papers for the appeal.

"The fact that this farce has been blamed on an administrative cock-up will come as little comfort to the public who will be left wondering how many more mistakes Justice Minister Cathy Jamieson can make."

We must not forget that this was an entirely avoidable fiasco Annabel Goldie Tory justice spokeswoman

Ms Sturgeon added: "The Scottish Executive were told time and time again to end slopping out in Scotland's jails but they failed to do so and now we are faced with hundreds of similar compensation claims from prisoners.

"While the executive had little choice but to appeal, it is not unreasonable to think that they should have made sure the paperwork was correct and the fact that it wasn't smacks of gross incompetence."

Scottish Conservative justice spokeswoman Annabel Goldie accused the executive of "gross ineptitude" and of having a "devil-may-care attitude" to taxpayers money.

'Degrading treatment'

She said: "Money will now be paid to convicted criminals rather than being spent on putting more police onto our streets or improving our public services.

"Sadly, a life of crime sometimes does pay under this government."

Ms Goldie added: "If they are not letting you out of jail early under the ludicrous automatic early release scheme, they are letting you escape from court, and now they might pay you compensation because of slopping out.

"We must not forget that this was an entirely avoidable fiasco."

Armed robber Napier was held in Barlinnie Jail

Napier raised a legal challenge in 2001 under the European Convention on Human Rights.

He was held at Barlinnie Jail after being arrested for failing to appear at the High Court on robbery, assault and abduction charges.

Lord Bonomy awarded him �2,400 after ruling that slopping out amounted to degrading treatment.

He said the practice violated articles three and eight of the convention and the common law "duty of care."