A Scot who has been challenging his US jail term for 30 years is awaiting a decision which could set him free - but then immediately face a retrial and a possible death sentence.

Tom Richey, who was jailed aged 18 for shooting two people and killing one while high on LSD, has been pushing for what he believes is a fairer sentence for his crime.

He was initially spared the death penalty and sentenced to 65 years in jail, but the latest twist in the case brings the potential of a legal process that could lead to Death Row.

The killer’s older brother Kenny was freed from Death Row in 2008 after serving 21 years in the State of Ohio for starting a fire that killed a two-year-old girl.

Richey’s own extensive defence reached back to when he had been a US Special Forces soldier stationed near Tacoma, Washington.

He had flown to the US at the age of 17 to enlist, it was claimed.

Larry Nichols, his now retired court appointed lawyer, recounted his client’s training coupled with his interest in the film First Blood as mitigation.

Mr Nichols said: “The day following the shootings, Tom turned himself in and confessed, which left me few cards to play with.

“Sixty-five years is three times higher than the standard sentence for murder, but it’s a great deal better than the death penalty.”

Richey, speaking in a telephone interview from Washington State Penitentiary, said: “Since entering prison, I’ve focused on educating myself and being a better person.

“People always judge you by your worst moment, but we’re a sum of many parts.

“That’s not to say I’m marginalising what I did. I senselessly took a life and there’s no undoing that, ever.”

A light at the end of the tunnel appeared when in 2004 the US Supreme Court announced that the procedures involved in sentencing defendants like Richey to long fixed terms was unlawful.

However the ruling wasn’t made retroactive, meaning it did not affect those who were sentenced prior to 2004.

Richey, who wrote his brother's biography, said: “It disappointed me, but I’m in no position to complain.

“Whether the length of my sentence is unlawful doesn’t mean it wasn’t the right price I deserve to pay.

“But I am human, so I still feel human desires, like the desire to be free.”

In November 2014, the Federal Ninth Circuit Court of Appeals held that an update of his conviction was a new judgement and that Richey is entitled to federal review.

A decision is expected from the federal Western District Court of Washington in the next few weeks.

It is a landmark case that has attracted great interest in the US legal establishment.

Lawyer Peter Aveno, a veteran of legal practice assigned to the Northwest Federal Public Defender’s Office in Seattle, said the case is critical.

He said: “Richey’s case is the first on record in the history of American jurisprudence, where a court has arbitrarily entered a judgement of conviction without satisfying the necessities of due process, such as the right to a trial by a jury of one’s peers.

“If the district court doesn’t order the state court to vacate the conviction, then they’ll effectively open the door to states to abolish the due process protections guaranteed by the sixth and 14th Amendments of the US Constitution.”

Richey believes he will be freed, but Mr Nichols does not agree that it will be clear cut.

He said: “In the event Tom’s conviction is vacated, he’ll return to square one.

“He’ll face the remaining original murder charge, a capital offence, and be subject to the death penalty again.

“Of course, it would be difficult to try such an old case, where evidence has been destroyed and witnesses have passed away and dispersed."