Abdul Wahid Rehman, 32, shot Leon Bickersteth, 32, at his home in Wortley in March 1998 with an old service revolver from the world wars after a £60,000 consignment of drugs Rehman was looking after went missing.

Rehman denied being the killer, but was convicted by a jury of the slaying at Leeds Crown Court in October 1999 and given a life sentence.

Despite there being no forensic evidence to link him to the killing, the prosecution relied on the fact that Rehman had boiled his trousers so hard in the washing machine that they shrank three inches.

A fact they claimed was consistent with him being present at the scene of the killing wearing that garment.

On October 4, 2001, the Home Secretary ruled that Rehman must serve a
minimum of 20 years behind bars for the murder before he can even apply for parole.

At Rehman's request, top judge, Mr Justice Irwin, sitting at London's High Court on Wednesday, reviewed the length of that tariff.

But far from being inclined to reduce the term, the judge said that, had he been sentenced today under much tougher sentencing guidelines now in force, a minimum term for 30 years, not 20, would probably have been imposed.

"However I must pass a period no longer than that set by the Home Secretary. Taking all those factors into account the proper minimum term is 20 years," the judge concluded.

After time spent on remand is taken into account, the ruling means Rehman can apply for parole in 2018.

However, he will only then be freed if he can convince the Parole Board he no longer poses a danger to society.