A FAMILY last night won its 50-year fight for justice after an inquest ruled the death of an airman during secret nerve gas experiments was unlawful.

Leading Aircraftman Ronald Maddison, 20, from Consett, County Durham, died in May 1953 after being exposed to the deadly agent sarin during experiments at Porton Down, in Wiltshire.

Yesterday, a second inquest into his death returned a verdict of unlawful killing.

The jury's ruling paves the way for the family to seek compensation - along with hundreds of other servicemen subjected to experiments at Porton Down from 1939 to 1989.

LAC Maddison died after sarin was dropped onto his arm at the Porton Down chemical warfare testing facility.

Winston Churchill's Government ordered the initial inquest to be held behind closed doors and it recorded a verdict of misadventure.

But after years of campaigning by the family, an inquiry was launched by Wiltshire Police in 1999. In 2002, Lord Chief Justice Woolf granted permission for a second inquest, which began in May this year.

LAC Maddison's sister, Lilias Craik, is recovering from a stroke and could not attend the end of the 64-day hearing.

Alan Care, lawyer for the Maddison family, said: "Sadly, Lilias Craik is unable to attend today, but she wishes me to say that after 50 years the family now know how and why Ronnie died and are pleased that the jury's verdict is unlawful killing by the state.

"The family now seek compensation. Given the facts that have now emerged, the family wish to fully support all veterans who were misled into attending Porton Down in their demand for a public inquiry."

The Father of the House of Commons, Labour MP Tam Dalyell, who has campaigned on the issue of Porton Down for decades, said he sympathised with veterans' calls for a public inquiry into the research and called for some kind of pay-out for them.

During the hearing in Trowbridge, Wiltshire, LAC Maddison's family claimed he and other military personnel were tricked into taking part in what they believed were harmless experiments to find a cure for the common cold.

The court heard how the test that claimed his life took place only nine days after a similar experiment resulted in the near-fatal poisoning of another volunteer, soldier James Kelly. But lawyers for the MoD said all servicemen who underwent chemical experiments at Porton Down were told beforehand.

Terry Alderson, 74, from Danby, near Whitby, North Yorkshire, said he was delighted with the decision.

"We have got a result for the Maddison family," he said. "This shows what liars the MoD were.

"We were sent in there like sheep. They treated us like human animals and we that are still alive are the lucky ones."

A spokesman for the MoD said: "The Ministry of Defence notes the jury's findings and will now take some time to reflect on these.

"We will be seeking legal advice on whether we wish to consider a judicial review.

"We don't believe the verdict today has implications for other volunteers. However, we will consider the implications."

Mr Alderson said outside the court: "It was Russian Roulette. Ronald Maddison was just the first.

"Reading between the lines, they have got away with murder. Our health was never monitored afterwards and nobody knows how many died."