He was granted U.S. citizenship in 1970, however and later retired to Miami Beach, Florida in 1973. In the mid-70s, Congressional Representatives Joshua Eilberg and Elizabeth Holtzman initiated a set of hearings that led the US Government Accountability Office (GAO) to investigate the handling of possible Nazi war criminal data. No mishandling was found, but as a result, a Special Litigation Unit for the investigation of Nazi war criminals was established in the INS.