After a 15-day trial at Nottingham Crown Court, jurors took less than four hours to unanimously find Colin Cheetham (61), guilty of murder.

Mr Justice Alastair MacDuff said: "It is difficult to understand how evil you are. You lack any sense of humanity.

"It is difficult to begin to comprehend the sheer fear that Stuart Ludlam must have felt as he moved, in your power, towards his death.

"This is an execution brutally carried out, with no remorse, of a man you never knew. He was an honest, decent human being. He was a fine man. A man of real worth. A million miles away from you."

The judge ordered a life sentence, with a 30-year minimum, which he stressed cannot be shortened.

He said it was highly unlikely Cheetham, who has diabetes, lymphoedema and cellulosis and walks with a stick - would live long enough to be released in 2040.

The court heard how Cheetham called a taxi, driven by Mr Ludlam, then lay in wait before shooting the driver twice in the head.

The killer was told he made one small, but crucial, mistake by using a credit card to top-up the mobile phone used to lure Mr Ludlam (43), to his death.

The judge said: "But for that you would likely have never been brought to justice. You decided to execute a man for your own pleasure and gratification - any man.

"You craved the act of being able to kill and watch from a distance as you got away with it. You were unconcerned about who you put to death.

"You have been convicted of murder on overwhelming evidence. You are an evil man and there is nothing to commend you."

The judge agreed with the prosecution argument that Cheetham had rehearsed his plan on drivers with other companies in the months prior to the killing.

He also agreed that pictures of the station - including an advertisement for Mr Ludlam's firm M.J's Taxis of Middleton by Wirksworth - found on Cheetham's cameras were chilling evidence of his dark scheme, rather than an attempt to produce a Christmas calender for friends as the defence had argued.

Cheetham, of Waingroves Road in Ripley, had said he provided a loaded gun to a man he knew only as Geoff, who wanted to steal drugs from a dealer who had got his sister addicted. He said the gun was to be a 'persuader' but would not be used.

Cheetham always denied murder and said he left the station after the first shot was fired, then later returned.

He said Geoff had threatened to harm him and his wife Jennifer if he refused to lend an illegal sawn-off .22 Rimfire Calibre shotgun, plus a silencer.

But the entire robbery story - which Cheetham had first told in March this year after initially denying having any involvement - was rubbished by the prosecution.

Police were unable to find any of the people mentioned, despite extensive searches.