Tagging would aim to reduce the number of delays

The Criminal Procedures Bill - based on a review by senior judge Lord Bonomy - was published by Justice Minister Cathy Jamieson, who said it would deliver a more "effective and efficient" system.

Tagging would be used in some cases to prevent trials being delayed because of witnesses failing to appear.

There are also proposals to extend the length of time a prisoner can be held on remand before the start of his or her trial.

At present an accused person can only be held in custody for 110 days from their first appearance in court.

Time limit

Under the proposals a preliminary hearing will have to take place within that time limit, with the trial date being set a maximum of 30 days later.

The extension is aimed at helping defence teams prepare their cases and cut the number of adjournments.

The law will also be changed so that an accused person will be freed if the time limit is exceeded, but can still be prosecuted.

Cathy Jamieson made the announcement

Preliminary hearings will become mandatory in the High Court, and fixed trial dates will be set so that victims and witnesses will know exactly when they must come to court.

The legislation proposes that sheriffs should be able to impose jail terms of up to five years instead of the current three years, almost halving the number of cases going to the High Court.

Prisoners who have fled from justice could be tried in their absence.

Witnesses who refuse to turn up at court could be placed on bail and, in a "small minority" of cases, be electronically tagged.

"This option would only be used in infrequent and extreme situations where it is expected the witness will not appear in court - not through fear of taking part in the proceedings but in a deliberate attempt to cause delay in the trial," said a Scottish Executive spokesperson.

There must be an end to the culture where cases are put off again and again Cathy Jamieson Justice Minister

Ms Jamieson said the reforms were part of "the most significant overhaul of our criminal justice system in 20 years".

She said: "These changes together form a radical and coherent package - but they will only work if implemented together and if judges manage the cases that come before them.

"There must be an end to the culture where cases are put off again and again, delaying the day of reckoning for the accused person.

"The modernised time limits will mean what they say. When a firm date is set, the trial will start on that date. This will reduce the stress and tension for victims and witnesses."

She added that electronic tagging would be made available while an accused person was on bail.

A review of court procedures was carried out

John Scott, of the Scottish Human Rights Centre, said that tagging of reluctant witnesses would be preferable to locking them up.

"There is far too much use of prison where it is unnecessary," he said.

"Tagging someone so that the authorities know where they are and can send the police round to get them rather than delaying a trial is fine.

"That is the sort of situation where it can be used without objections."

However, he said the legislation would need to be "carefully framed" .

Safeguards and rights of appeal were required so that any mistakes made could be corrected as soon as possible.

The Scottish National Party warned that pitfalls exist in the tagging proposals.

Justice spokeswoman Nicola Sturgeon said: "Tagging witnesses would be a very extreme measure to ensure that people turn up in court to give evidence and I fear that it will be fraught with difficulties.

Proposals which make the whole system so intimidating that witnesses may never come forward in the first place are clearly regressive Annabel Goldie Tory justice spokeswoman

"Many witnesses who fail to turn up in court will have been intimidated and may be in fear of their lives. They need support and protection, not punitive measures.

"It is also the case that most witnesses - certainly in relation to the trial in which they have been cited to give evidence - have done nothing wrong. They are neither accused of nor guilty of any crime."

Tory justice spokeswoman Annabel Goldie also raised concerns over the tagging plans.

"While of course there is a need to ensure that witnesses attend when required, proposals which make the whole system so intimidating that witnesses may never come forward in the first place are clearly regressive," she said.

Ms Goldie also repeated her party's opposition to scrapping the 110-day rule, describing it as a "retrograde step" that sought to treat the symptom of the problem rather than address the underlying cause.