Arron Bamborough, 24, and Roland Thorp, 27, had planned to rob a drugs dealer who lived in the same road in Putney, south-west London. Instead, they killed Mr Jacks in the living room of his house, where he was watching television.
Judge Angus Stroyan, sentencing the two men at the Old Bailey, described the killing as 'a cruel and merciless murder' which would outrage ordinary people. 'You picked the wrong house, the wrong man and the wrong day.'
Mr Jacks, a senior trainee with the leading accountancy firm Ernst & Young, was about to take his accountancy exams when he was shot last June; he had taken a break from studying and was watching the Test match on television.
Unknown to him, Bamborough, Thorp and a third man - never caught - were watching his home for the expected delivery of 118kg of cannabis. Detectives later established that the drugs were due to arrive at a nearby house, but the courier had already been arrested in Spain.
By a quirk of fate, Mr Jacks' flatmate drove up in a car similar to that of the expected courier and dropped off a bag of clothes. The three watchers wrongly concluded he was the courier.
The court was told how the three men kicked down the door of Mr Jacks' home, beat him up and demanded to know where the drugs were. Neighbours heard Mr Jacks scream 'I don't know' before he was shot in the leg with a sawn-off shotgun. He bled to death within minutes.
Thorp, who police believed fired the fatal shot, was on parole for stabbing two men in a wine bar. Bamborough has earlier convictions, mostly for stealing cars; his parents, who insist he is innocent, hurled abuse at the jury.
Mr Jacks was a pupil at Rugby School and went on to study natural science at Sidney Sussex College, Cambridge, obtaining a 2:2 degree. After graduating, he was offered a number of jobs and plumped for Ernst & Young.
Colleagues there said he was held in high regard and had a promising career ahead of him.
In court, Mr Jacks' parents sat hand in hand. Asked her reaction to the sentence given to her son's killers, Patricia Jacks said: 'It is too soon to ask me. I do not believe in capital punishment because no one has the right to take anyone's life.
'I know it makes him sound a goody two-shoes but he was was brought up with principles. He was a straight guy - straight down the middle,' Mrs Jacks said.
Mrs Jacks, 48, who has since retired from her job as an office manager, said her son's death had been like 'losing a limb'. Now, she said, her family was enough to live for: 'We are very lucky. We have each other and we have Martin's younger brother, Stuart, so you just tighten the nucleus. It was four and now it is three.'
She added: 'We can never say Martin's life was wasted, because he achieved so much, even in his short life. We are very proud of both our sons - both good, honest and open people.'
Ernst & Young have agreed to sponsor an award in memory of Mr Jacks. The pounds 400 prize will be awarded annually to the top three students at his old Cambridge college.
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