A couple are hoping a new Supreme Court ruling could see their son freed after he was jailed for his part in a murder.

Papers have already been lodged to appeal against Antony Parsons’ conviction and 23-year minimum sentence under the joint enterprise law, which followed the murder of drug dealer Ben Chantler in Folkestone in January 2006.

His parents, Jesse and June Parsons, say they are the closest they have ever been to getting their son’s conviction overturned, following the Supreme Court’s ruling on Thursday.

Scroll down for video

A panel of five judges ruled that hundreds of cases could have been misinterpreted for more than 30 years following a change to the law in 1984.

Mrs Parsons said: “It’s a huge step, not just for our son but for hundreds. We just burst into tears. It’s just the relief really.

“I still find it really hard to believe that something’s going to go right for a change.”

Mr Parsons said: “It feels quite strange to think we are part of a major change to this country’s legal system for the better.”

The couple, who now live on the Romney Sands Holiday Park in Greatstone, are members of a national campaign group called Jengba (Joint Enterprise: Not Guilty By Association) which has fought for a change to the law for the past decade.

They say they want the law to be fairer for secondary party defendants who do not have control over another person’s actions, removing the murder conviction and associated mandatory life term.

Lawyers are now preparing to take a case to the Appeal Court again and Mr and Mrs Parsons expect to hear in the next few weeks whether the appeal will be heard.

Mrs Parsons said: “If they say it was wrong he can walk out with us.

VIDEO: Parents hope law change could see their son freed. Matt Leclere reports

“If they decide it’s been overturned he’s been there 10 years and wasted 10 years of his life, or they could come back with a deal with him like manslaughter and time served.

“It’s with the barristers, solicitors and Antony, so it’s down to them now and we’ve just got to wait – and fingers crossed.

“It’s a new start for us and new start for Antony. We hope we can just get on and get him home.

“We’re getting no younger and if he’d been in there for another 14 years there’s a chance we wouldn’t have been here if he came out.”

The joint enterprise law states that defendants can be convicted by having the “foresight” that a killing would take place or at the very least serious harm would be caused – even if they don’t physically take part or are even in the building when it happens.

Under the doctrine, police and prosecutors only have to prove that the defendant was involved to charge them with murder.

“It’s one law to catch all, they use it more for gang crime. But with gang crime you can never really nail it down to one single person,” Jesse said.

“What they’ve said is because you were there you must’ve known he was going to do it. But they’re looking into that more.

“In Antony’s case there was no forensic evidence used at all. He says he’s in for giving my mate a lift.”

The judicial select committee heard evidence last year which agreed the law should be changed.

Mr and Mrs Parsons say they and their son still feel sorry for Mr Chantler and his family for what happened.

But they have always maintained their son had no idea Stuart Benson was going to kill Mr Chantler when they drove to his Denmark Street house.

They maintain that as their son only saw the weapon after Benson pulled the trigger and had parked five streets away in a car which needed bump starting, it was not planned by the pair.

Therefore, they argue he had no foresight of the murder taking place.

Mr Parsons said: “The police and CPS didn’t have to prove that you knew you were going to do it the fact you were there was enough.

“This rule change, going back to what it was, the police without shadow of a doubt have to prove you had the same intention as the person that committed it.”

Parsons is currently in prison in Nottingham having served 10 years of his minimum term.

“While he’s been in there he has been trained in an NVQ assessor’s course for cookery, he’s a qualified gym instructor,” Mrs Parsons added. “Although it’s a chubby picture of him here, he’s a lot thinner. He’s not just been sitting around doing nothing.”