In Schilling v. Rogers, Attorney General (1959), the U.S. Supreme Court dealt with a case involving an American citizen who had been residing in Mexico for several years and was denied re-entry into the United States due to his alleged Communist affiliations. The plaintiff, Mr. Schilling, argued that he had not voluntarily renounced his citizenship and therefore could not be barred from returning to the country of his birth under Section 349(a)(6) of the Immigration and Nationality Act which states that any person "taking an oath or making a declaration…to a foreign state" would lose their nationality if they were also citizens of said foreign state. The court ruled against Mr. Schilling stating that while living in Mexico he had sworn allegiance to its government as part of obtaining employment there; this act constituted voluntary expatriation according to U.S law at the time despite him arguing it was done under duress because he needed work. This ruling upheld previous decisions by lower courts on similar cases where individuals lost their US citizenship after swearing loyalty oaths abroad even when such actions were taken out of necessity rather than genuine political conviction.

In the dissenting opinion for Schilling v. Rogers, Justice Brennan disagreed with the majority's decision to uphold a law that stripped U.S. citizenship from individuals who deserted military service during wartime. He argued that this punishment was too severe and violated the Eighth Amendment’s prohibition against cruel and unusual punishments. Furthermore, he contended that denationalization could lead to statelessness which is an extreme form of punishment not suitable for desertion crimes in his view. Brennan also pointed out inconsistencies in how different types of deserters were treated under existing laws; some would lose their citizenship while others wouldn't depending on when they committed their crime or whether it occurred during peacetime or war - a distinction he found arbitrary and unfair.