A man fatally shot by the FBI more than two years ago in New Orleans East agreed months before his death to cooperate with the bureau in its investigation of a local heroin ring but soon broke off contact with federal authorities, according to newly unsealed court documents.

The court filings raised fresh questions about the fatal shooting of Allen Desdunes, 37, an alleged drug dealer-turned-government informant who briefly reported to the bureau on a daily basis before changing cellphones and apparently reneging on an agreement that had kept him out of jail even after investigators found several thousand dollars worth of heroin in his vehicle.

The documents, filed under seal about a week before Desdunes’ death in July 2013, were made public last week as part of a wrongful-death lawsuit filed by Desdunes’ family. The lawsuit claims he was unarmed at the time of the shooting and “did nothing to provoke” the FBI’s use of deadly force.

The FBI has refused to discuss the shooting and a subsequent inquiry that cleared John Sablatura, the agent who fatally shot Desdunes. Sablatura’s involvement, like many aspects of the case, had been kept secret until last fall, when a federal magistrate ordered his identity revealed.

The terms of Desdunes’ deal with the government remain unknown. It’s unclear, for instance, whether the FBI permitted him to continue dealing drugs in exchange for information he passed along about his heroin provider. An FBI spokesman declined to comment Monday.

Stephen Haedicke, the civil rights attorney representing Desdunes’ family, said he could not comment on the unsealed court filings because of a protective order governing the exchange of information in the civil case.

The bureau’s use of confidential informants has generated controversy for decades, in part because many of the informants are criminals. A USA Today article published five days after Desdunes’ death found that the FBI allowed its informants to break the law 5,658 times in a single year — leeway the government officially refers to as “otherwise illegal activity.”

Local and state law enforcement authorities also frequently rely on confidential informants.

“Although it is legally permissible for the FBI to use informants in its investigations, special care is taken to carefully evaluate and closely supervise their use so the rights of individuals under investigation are not infringed,” the bureau says on its website. “The FBI can only use informants consistent with specific guidelines issued by the attorney general that control the use of informants.”

The newly unsealed court filings reveal that the FBI had flagged Desdunes in early 2013 as belonging to a “heroin distribution organization” that had been under investigation for more than two years. On May 1, 2013, agents tailing Desdunes spotted him making “what appeared to be hand-to-hand (drug) transactions with numerous individuals.”

Investigators stopped Desdunes and found about 100 grams of heroin in his black Nissan Murano. Instead of going to jail, the court filings show, Desdunes accompanied agents to the FBI’s local field office, where he admitted selling heroin, “provided some information on his heroin supplier and agreed to cooperate” with the FBI New Orleans Gang Task Force.

“Because of his agreement to cooperate, Desdunes was allowed to leave and was required to maintain constant telephone contact with Special Agent Jonathan Wood,” an FBI investigator wrote in an application for a search warrant.

At first, Desdunes communicated with Wood every day, the investigator wrote, but he stopped calling after about a week. The FBI kept trying to reach Desdunes, who was known as “Big Al,” but he did not answer.

A few weeks later, an unnamed informant gave the FBI Desdunes’ new cellphone number. Days later, agents surveilling Desdunes watched as he disposed of “heroin-laced packaging material” in the parking lot of the Motel 6 on the Interstate 10 Service Road in New Orleans East, the records show.

At the time of the shooting, the FBI had been tracking Desdunes’ movements for weeks, monitoring GPS data from his cellphone. The court-approved surveillance led investigators to believe that Desdunes, after failing to touch base with his FBI contact, was peddling drugs out of the Motel 6 and perhaps stashing heroin at a separate residence.

The FBI, joined by New Orleans police, confronted Desdunes at the motel on July 30, 2013. But the bureau has provided no accounting of what prompted Sablatura to open fire on that occasion.

According to the wrongful-death lawsuit, Desdunes and another man, Terry Lane, were driving out of the parking lot of the Motel 6 when two unmarked cars approached at high speed and rammed their vehicle. The airbags in Desdunes’ car deployed, the lawsuit claims, and “seconds later a gunshot or gunshots were fired” by the officers.

The lawsuit claims no weapons were found in Desdunes’ vehicle.

The civil case is set for trial in May.

Follow Jim Mustian on Twitter, @JimMustian.