Protest over Royal Marine's Afghanistan murder conviction
Protesters have gathered outside Parliament to call for the immediate retrial of a marine convicted of murdering a wounded Afghan insurgent.
Royal Marine Sgt Alexander Blackman was given a life sentence by a court martial for the 2011 incident. He must spend at least eight years in prison.
Supporters say his conviction could be reduced to one of manslaughter.
Blackman's wife, Claire, called for a retrial so evidence "missed" during the 2013 trial could be considered.
The killing, on 15 September 2011, took place after a patrol base in Helmand province came under fire from two insurgents.
One of the insurgents was seriously injured by gunfire from an Apache helicopter sent to provide air support.
Footage from another marine's helmet-mounted camera showed Blackman then shot the Afghan prisoner in the chest with a 9mm pistol.
Blackman, of Taunton, Somerset, maintained that he believed the insurgent was already dead when he shot him.
The 41-year-old unsuccessfully challenged the sentence in the Court Martial Appeal Court, but successfully had his sentence reduced from a minimum of 10 year to a minimum of eight years.
Supporters, including Royal Marines wearing green berets, joined Blackman's wife and MPs outside Parliament to call for an immediate retrial.
Mrs Blackman told the BBC: "The opportunity to go back to the courts and run this case thoroughly and include evidence that was missed before is an opportunity we have to take.
"We are hopeful that this review will happen. It's been a difficult time as you would expect.
"I can't tell you how wonderful it is to have this sort of support."
Richard Drax, Conservative MP for South Dorset, said Blackman was not a "cold blooded killer" but a man who "was pushed to the limit, who made a mistake".
He said he hoped the case would be considered by the Criminal Cases Review Commission "before Christmas", adding that Blackman believes the prospect of a lesser manslaughter charge was "not explored at the first trial".
"It is not a matter of saying he didn't do it and shouldn't be punished, that's not what we are saying. We are just saying we want a retrial so that we get, hopefully, a better conclusion," the MP said.
Rally co-organiser Jeff Little said the government had "let down one of our own".
He said Blackman had been under immense pressure, having led a team of 15 men for five months, adding: "They were aware that hundreds of their comrades had already been killed or maimed by IEDs (improvised explosive devices). The psychological impact was devastating."
A Ministry of Defence spokeswoman said regulations prohibited members of the military from attending political protests, marches, rallies or demonstrations.
"Any gathering which seeks to protest against a decision taken by the legal system or the government falls into this category," she said.