Neal Sher, 74, a lawyer who for 11 years ran the federal office that rooted out WWII-era Nazis in the United States and moved to revoke their citizenship and deport them died Oct. 3 at his home in Manhattan.

Mr. Sher joined the newly-formed Office of Special Investigations, the Justice Department’s Nazi-hunting department, as a litigator in 1979 and became its director four years later. Its targets were often individuals who had lied to enter the United States after WWII to conceal their Nazi past.

The cases Mr. Sher prosecuted or oversaw included those of John Demjanjuk, who was accused of having been a death camp guard and deported to Germany; Archbishop Valerian Trifa, who, as part of the antisemitic Iron Guard of Romania, was reported to have instigated a pogrom in 1941 against Jews in Bucharest; and Arthur Rudolph, who was accused of “working slave laborers to death” in the V-2 rocket factory in Germany before becoming the project manager of NASA’s Saturn 5 rocket program, which was critical to the Apollo spaceflights. Mr. Trifa was deported to Portugal, and Mr. Rudolph surrendered his citizenship and agreed to go to West Germany rather than fight deportation.

In 1986, Mr. Sher recommended that Kurt Waldheim, a former secretary-general of the United Nations, be denied entry to the United States because of his service as a German Army lieutenant in the Balkans during brutal campaigns against Yugoslav partisans and mass deportations of Greek Jews to death camps. Attorney General Edwin Meese III put Mr. Waldheim — who had been elected president of Austria by then — on a list of people who were barred from entering the United States.