The executive faces further compensation claims

Judges heard on Wednesday why the executive failed to contest a decision that the practice was "degrading".

At the Court of Session in Edinburgh, executive lawyers apologised for missing the legal deadline.

In a lengthy explanation they said a senior clerk and her deputy had both failed to lodge the appeal papers.

About 1,200 prisoners have to slop out in five prisons across Scotland.

We are glad that the court has given us an opportunity to appeal against Lord Bonomy's judgement Scottish Executive spokesman

Lord Cullen said he was satisfied that there had been an inadvertent mistake and allowed the executive more time to lodge their appeal.

A spokesman for the executive said: "We are glad that the court has given us an opportunity to appeal against Lord Bonomy's judgement and look forward to presenting our arguments to the Inner House in due course.

"In the meantime, a full investigation is under way into what went wrong in this particular case together with a review of procedures for handling litigation.

"We will consider what further steps may be necessary when the investigation has been completed."

The Inner House of the Court of Session, Scotland's supreme civil court, specialises in appeals.

The executive's QC, Neil Brailsford, gave the court a lengthy explanation about how a senior clerk had been tasked with lodging the papers on the day of the deadline, but had gone on a training course and asked her deputy to do it for her.

Her deputy had tried, but she did not have all the necessary documents with her, so officials would not accept it.

The court heard that not only did the clerk not phone to arrange for the paperwork to be delivered, but also did not tell anyone in the executive what had happened.

'Inadvertent mistake'

The executive argued that under court rules that amounted to an inadvertent mistake, a position that was accepted by Lords Cullen, Hamilton and Menzies.

The legal arguments follow the case of Robert Napier, who raised a challenge under the European Convention on Human Rights.

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

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

A 21 day deadline to appeal the legal judgement was missed, so the executive had to return to the courts to ask for more time.

More claims

Mr Napier's lawyer, Tony Kelly, said that the grounds of appeal only covered part of Lord Bonomy's ruling and that ministers did not seek to reverse his decision that Napier was entitled to damages.

He also claimed that the appeal process, expected to extend well into next year, would not stop other prisoners bringing slopping out claims to court.

He said: "I am acting now for approaching 400 and more and more are coming forward every day."

During the hearing into Mr Napier's claim, ministers had argued that their attempts to modernise the country's prisons had been affected by a rising jail population and cuts in funding.

They had planned to abolish slopping out by this year but the target is now 2008 at the earliest.