In the United States v. Lepowitch et al., 1942, the Supreme Court ruled on a case involving fraudulent impersonation under federal law. The defendants, Mr. and Mrs. Lepowitch, were convicted of falsely representing themselves as agents of a company to induce another party into selling them property at a reduced price. On appeal, they argued that their conviction was invalid because there was no proof that their deception caused actual harm or loss to the victim - an element they claimed was necessary for conviction under the relevant statute (18 U.S.C §76). However, in its decision authored by Justice Felix Frankfurter, the Supreme Court disagreed with this interpretation and upheld their convictions. The court held that causing harm or loss is not required for conviction under this statute; it's enough if one fraudulently impersonates someone else with intent to defraud – whether successful or not doesn't matter legally speaking. This ruling clarified legal standards regarding fraudulent impersonation crimes and affirmed broad protections against such deceptive practices.

The dissenting opinion in the United States v. Lepowitch case was not available in the source material, and it appears that there may have been no formal dissent to the majority decision. The Supreme Court unanimously ruled that misrepresentation of identity with intent to defraud is a punishable offense under federal law, even if no property or money has been obtained as a result of such deception. This ruling expanded on previous interpretations of fraud statutes which had required tangible loss for conviction.