Federal authorities are urging a judge to bar the public from the courtroom while inspectors from the Witness Security Program testify in the case of former New England Mafia boss Francis "Cadillac Frank" Salemme.
The U.S. Marshals Service says in court documents that the public should be seated in a different courtroom and audio of the testimony should be broadcast.
Judge Allison Burroughs has already said the officials who regularly meet with program participants can use a pseudonym. But she previously rejected the prosecutors' request to install a screen so the public can't see them.
The Marshals Service says disclosing their identities could be devastating, calling it a "question of life and death."
Salemme is on trial for the 1993 death of a nightclub owner. Salemme was previously in the witness protection program.