NEW ORLEANS — A man whose convictions on charges he killed five people at a 1995 party were overturned by the U.S. Supreme Court last year is suing the Orleans Parish District Attorney’s Office, accusing prosecutors of concealing evidence and lying to cover up their alleged misconduct.

Juan Smith’s suit, filed Wednesday in federal court, seeks at least $24 million in damages. Former Orleans Parish District Attorney Harry Connick, whose office prosecuted Smith, and Leon Cannizzaro, the city’s current district attorney, also are named as defendants.

In January 2012, the Supreme Court ordered a new trial for Smith, who spent more than 16 years on death row at the Louisiana State Penitentiary in Angola.

“We are preparing to try him again,” Cannizzaro spokesman Christopher Bowman said Thursday.

Bowman said he hadn’t seen the lawsuit and couldn’t comment on it.

Connick’s office never gave Smith’s lawyers copies of a witness’ inconsistent statements about whether he could recognize or identify Smith as one of the killers in the so-called “Roman Street shootings.” The statements by Larry Boatner, the sole alleged eyewitness to the shootings, were contained in police files that Smith’s lawyers first obtained in 2004.

“Boatner himself spoke to the police on four separate occasions in the immediate aftermath of the shootings,” Smith’s suit says. “On those occasions, he gave conflicting accounts of whether, and to what extent, he could identify any of the perpetrators.”

The Supreme Court’s ruling in Smith’s case was the second time in two terms that it dealt with New Orleans prosecutors’ alleged violation of its obligation to turn over evidence that could prove a defendant’s innocence.

In 2011, a divided Supreme Court overturned a $14 million judgment given to former death row inmate John Thompson, who was convicted of murder after New Orleans prosecutors withheld evidence from his defense lawyers. In a dissenting opinion, Justice Ruth Bader Ginsburg said Thompson deserved damages for “the gross, deliberately indifferent and long-continuing violation of his fair trial rights.”

Smith also was convicted of separate murder charges stemming from shootings that killed three people roughly a month before the Roman Street shootings. Testimony about the Roman Street shootings was introduced during the penalty phase of the other trial, which resulted in a death sentence.

The victims of the triple murder included the ex-wife and 3-year-old child of former New Orleans Saints defensive back Bennie Thompson. Smith’s appeal in that case is on hold pending the outcome of the Roman Street case.