Vincent Asaro, whose arrest last year had supposedly closed one of the country’s most infamous unsolved crimes more than three decades later, was cleared of murder, extortion and other crimes by a jury in Brooklyn federal court on Thursday.

The verdict is a rebuke to federal prosecutors in what may be one of the last major Mafia trials to stem from organised crime’s heyday in New York decades ago.

Prosecutors had said Asaro waited in a decoy car with another gangster, Jimmy Burke, near John F Kennedy International Airport in New York, as a group of masked men robbed a Lufthansa Airlines cargo building of $US6 million in cash and jewels.

The caper was memorialised in Martin Scorsese’s Academy Award-winning 1990 film, in which Robert DeNiro played a character based on Burke, long believed to be the mastermind of the robbery.

Asaro, whom prosecutors claimed is a third-generation member of the Bonanno crime family, was also charged with strangling a suspected informant to death with a dog chain in 1969, soliciting the murder of a relative and robbing an armoured car, among other crimes.

The three-week trial featured numerous former organised crime figures whose testimony painted a picture of the violent life of a New York Mafioso.

Among those witnesses was Asaro’s cousin, Gaspare Valenti, who wore a wire for years and whose co-operation with authorities led to Asaro’s arrest in January 2014.

Valenti claimed to be one of the robbers in the Lufthansa heist, delivering from the witness stand a riveting account of the infamous crime.

Until Asaro’s arrest, the only man ever charged in connection with the robbery was a Lufthansa employee who functioned as the inside man.

But defence lawyers argued successfully that Valenti, and the other co-operators, were professional liars who delivered false testimony in exchange for payments and promises of leniency.

“The government has become the pension plan” for former mobsters, Asaro’s lawyer Elizabeth Macedonio told jurors in her closing argument.

-Reuters