Prosecutors are seeking to shield the identities of two U.S. Marshals Service’s Witness Security Program inspectors by blocking them with a screen and calling them by a pseudonym when they testify against former New England Mafia godfather Francis “Cadillac Frank” Salemme.If approved by U.S. District Court Judge Allison D. Burroughs, Salemme’s trial courtroom will remain open to the public; however, only the accused murderer and his jury will be able to see the witnesses.