Early in 1944, in preparation for his case to go to trial, John Rogge (the prosecutor in United States v. McWilliams) wrote to Joseph Roos of the Jewish Community Relations Committee in Los Angeles to inquire about several potential witnesses. Both Roy Arnold and Charles Young were agents who had collected data against the accused seditionists; Rogge requests the information from Roos, and also requests the identity of another individual, known as "Informant B". 11 x 8.5 in.