In January 2005 the 6th Circuit Federal Court of Appeal in Cincinnati overturned Mr Richey's death sentence, demanding that the state of Ohio either release Richey or re-try his case within 90 days.

Since then legal moves from the Ohio authorities have kept the Scotsman in gaol despite calls from Amnesty International and others that he ought to have been released immediately.

This ruling was then appealed to the Supreme Court, which decided in November that the 6th Circuit Court should reconsider their initial ruling.

Mr Richey was convicted of arson and murder in the state of Ohio in 1986 and sentenced to death in January 1987.

He has been on death row for nearly 19 years but has always protested his innocence. Since his conviction evidence has emerged casting serious doubt on Mr Richey’s guilt.

Following the initial re-trial ruling...

Amnesty International UK anti-death penalty campaigner Sara MacNeice said:

"While Ohio has the right to seek a re-trial, we are nevertheless extremely disappointed that it has already taken over 18 years for deeply flawed capital trial to be re-examined.

"Many aspects of Mr Richey’s case - including a poor-quality original trial and a legal process making it virtually impossible to admit fresh evidence - show exactly why the death sentence should never be imposed in the first place.

"Given the present situation, we are now calling for a fair re-trial to be mounted without delay and for the state of Ohio to specifically rule out the death penalty in Mr Richey’s case."

Clive Stafford-Smith, the leading British-born US death penalty lawyer and Legal Director of Reprieve who has campaigned on behalf of Kenny Richey for 15 years, said: "A man who is as patently innocent as Kenny should not be forced to endure the agonising wait that will accompany a retrial – he has already spent 18 years sitting on death row for a crime he did not commit.

"If anyone were to sit down and look at the facts of this case, they would realize that the prosecution’s evidence is weak. There was no physical evidence linking Kenny to the crime. The prosecution’s major witnesses have changed their story. I find it hard to believe that the Ohio authorities can not find better uses for their tax payers' dollars." Mr Richey, who has a Scottish mother and grew up in Edinburgh, is also the subject of a longstanding campaign from a Scottish woman, Karen Torley. Ms Torley, now engaged to Kenny, said:

"I am disappointed because this has taken so long for Kenny to receive justice. He has already endured over 18 years on Ohio’s death row when all evidence shows that he’s an innocent man. However, a new trial will prove that he was innocent all along."

For several years Amnesty International, Reprieve and others have been urging the Ohio state authorities to allow Kenny Richey the opportunity to have fresh evidence heard.

Campaigners have also been pressing the UK government to keep up pressure on the US authorities in line with the government’s policy of opposing the death penalty in all instances. Last year the government confirmed that it has a "comprehensive lobbying strategy" over Richey’s case.

The Lib-Dem MP for Orkney and Shetland Alistair Carmichael has led the campaign over Kenny Richey in Parliament. Mr Carmichael has asked numerous parliamentary questions about the Richey case and personally visited Mr Richey in February 2004.

Mr Carmichael said:

"I am very surprised by today’s decision. While I welcome the fact that Kenny Richey will now be able to clear his name, it is regrettable that an innocent man will have to spend still more time on death row.

"Given the very strong ruling by the Appeal Court in January I think there is case for releasing Kenny now. I find it hard to believe that anyone looking objectively at the facts surrounding Kenny’s case can conclude that he is a guilty man.

"It is important that in the weeks ahead the British Government does all it can to assist Kenny. They have shown a willingness to act in the past and their active involvement must be maintained."

To find out more about the Kenny Richey campaign