BOSTON — Thirty-three years, two months and five days.
That is how long Peter Limone sat in prison, pinned by a murder conviction that just last month, after endless appeals, was finally vacated. This week, a judge confirmed that Limone was officially free and the case against him dropped.
"It was disgusting, what was done to him," William T. Koski, a lawyer for Limone, said. "It should be chilling to everyone else."
What was done to Limone, 66, became overwhelmingly clear only in recent weeks: He was effectively framed by a hit man cooperating with prosecutors and left to languish by FBI agents who apparently knew he was innocent but never spoke out.
In proceedings here that have stretched through several years, a federal judge turned up instances of FBI misdeeds so disturbing that they prompted a Department of Justice task force investigation and the establishment of federal guidelines on how agents are to interact with informants and what they must tell prosecutors about those relationships.
Testimony has painted some FBI agents as corrupt, and others as so intent on cracking the Italian mob in New England a generation ago that they literally let "top echelon informants" get away with murder.
Beginning in 1977, John Cavicchi, a lawyer, had fought to clear Louis Greco, who had been convicted along with Limone and four others for the 1965 murder of Edward Deegan, a small-time criminal. The main witness against them was the late Joseph Barboza, a hit man also known as The Animal, who later admitted that he had fabricated much of his testimony.
Cavicchi's efforts failed; Greco died in prison in 1995. But with Limone now as his client, he began building a new line of defense showing that Barboza, the hit man, had been offered all kinds of inducements by the authorities to testify as he did.
Then came a pivotal moment: In December, the task force released some explosive documents that showed that informants had told the FBI beforehand that there would soon be a hit on Deegan and said who would do it. An agency memo after the crime also listed the men who had apparently been involved. Neither list included Limone or Greco.
The implications were shocking: FBI agents had good reason to believe that Limone, Greco and two others were innocent, yet had done nothing to free them, apparently in order to protect their own informants, who were the real culprits. Also, it appeared they had done nothing to prevent the murder.
The two other men cleared by the FBI papers were Joseph Salvati, who got out of prison in 1997 when the Massachusetts governor commuted his sentence, and Henry Tameleo, who died in prison.
Harvey A. Silverglate, a Boston defense and civil liberties lawyer, said the case showed that offering criminals leniency for implicating others is dangerously prone to producing wrongful convictions.
"There are people on death row who've been convicted by these techniques," Silverglate said.
The FBI and federal prosecutors here declined comment on Limone's case.