A teenager has been found guilty of the murder of jeweller Marian Bates.
Peter Williams was said to have helped the gunman escape
Peter Williams was convicted of the killing by a jury at Stafford Crown Court on Monday.
Mrs Bates, 64, was shot dead as she shielded her daughter from armed raiders at the Time Centre in Nottingham in September 2003.
Williams, 19, of no fixed address, had denied murder. The prosecution alleged he helped a gunman to escape from the Time Centre after the shooting.
Mrs Bates stepped in front of her daughter, Xanthe, in an "instinctive act of bravery" when a gunman threatened her family at their shop in Arnold, Notts.
Police said after the verdict that they believed the suspected gunman, James Brodie, had been murdered.
Mrs Bates' husband, Victor, picked up a fencing sword in a bid to stop the two masked men from escaping in the raid but was beaten to the ground with a crowbar.
He said after the guilty verdicts: "We are pleased for the people of Nottingham as well as ourselves.
"It's not an end but it's the beginning of the end. It's some peace for Marian at last."
Marian Bates died in an armed robbery at the shop
He praised the "foot soldiers" of Nottinghamshire Police but added he was still critical of the force's management.
The jury was told Williams and the gunman, who has never been identified, entered the store wearing crash helmets on 30 September 2003.
Gregory Dickinson QC, prosecuting, told the trial that Williams was one of the robbers, but not the man who pulled the trigger.
"The identity of the gunman remains uncertain. There is some evidence that it was a man called James Brodie but he has disappeared and cannot be found," Mr Dickinson said.
Det Supt George Frame, of Nottinghamshire Police, said after the case: "We have information and intelligence that would suggest that he has been murdered.
"But that is not evidence and until we have conclusive evidence, he is still a missing person and enquiries are on-going to trace him."
Williams was also convicted of causing grievous bodily harm with intent to Mr Bates, possessing a firearm with intent and conspiracy to rob the store.
Dean Betton, 23, of Broxtowe, Nottingham, and Craig Moran, 22, of Bestwood, were convicted of conspiring to rob the shop on Front Street.
Lisa Unwin, 23, from Bestwood, Nottingham, was found guilty of conspiring to pervert the course of justice, along with Moran, by providing him with a false alibi.
Det Supt Frame said: "What you have seen in there over the last few weeks are members of Nottingham's criminal underclass, who are causing the society of Nottingham a lot of problems.
"Hopefully, they will get the sentences they deserve and Nottingham will be a better place for it."
The four will be sentenced on later dates.