The man who shot Craig Hodson-Walker was a convicted robber who lied repeatedly to escape justice for the killing.
Anselm Ribera, who owes his unusual surname to a Spanish-Irish mother, had claimed he had been out jogging at the time Mr Hodson-Walker, 29, was shot through the heart as he tried to fend off a masked gang at the post office.
But he was brought to justice by a combination of CCTV footage and mobile phone evidence which proved his version of events was a lie.
Ribera had already served time in prison for robbing another post office seven years ago.
During that robbery on February 25, 2002, a concrete block was hurled through a glass security screen at a post office branch in Redditch Road, Kings Norton, before Ribera and another man made off with £4,300 in cash.
The father-of-one, whose blood was found at the scene, admitted his role in the earlier offence and was jailed for six years, but was released from prison on licence in October 2005.
At the time of the Fairfield murder, Ribera had lost his job as a drain clearance worker because he had been given a driving ban.
The gunman admitted during his trial that he had little to do with his father, who originates from Barbados, but said he was close to his mother.
During several hours in the witness box, Ribera repeatedly refused to answer questions about mobile phone evidence linking him to the fatal shooting despite being ordered to do so by the trial judge.
He told the jury he was friends with Declan Morrissey and knew that Christopher Morrissey had previous convictions and had also served time in jail.
All Ribera's co-defendants were captured on CCTV visiting his flat 72 hours before the murder, but he claimed he had simply been lending them some money to "sort out" his mother's garden.
Ribera also told jurors he was out jogging on the morning of the killing, embarking on an "extensive" run which covered at least eight or nine miles before ending at his mother's home.
Giving evidence in the eighth week of his trial, the 34-year-old said he had set off in the dark for an early morning jog, possibly as early as 5.21am, on January 9.
The defendant, who had heroin worth around £500 on him when he was arrested, said: "I would most definitely have gone for a run on that particular morning if I was going out at that time."
But Ribera had been captured on CCTV at a BP petrol station at 6.15am on January 9 after pulling up in a Ford Mondeo later used as a getaway vehicle at Fairfield.