In the case of Baumgartner v. United States (1943), the U.S. Supreme Court ruled that a Swiss national, who had been living in America for over 40 years but never applied for citizenship, could be deported back to Switzerland due to his conviction on charges of sedition during World War II. The defendant argued that he should not be deported because he was technically stateless and did not have any allegiance to Switzerland or any other foreign power at the time of his offense. However, the court rejected this argument stating that under immigration law, an alien is anyone who has not been naturalized as a citizen regardless of their political affiliations or lack thereof. Therefore, even though Baumgartner considered himself stateless and had lived in America for many years without applying for citizenship, he was still subject to deportation upon being convicted of a crime involving moral turpitude.

In the dissenting opinion for Baumgartner v. United States, Justice Frank Murphy argued that the majority's decision to uphold Baumgartner's conviction was a dangerous precedent that threatened civil liberties. He contended that there was insufficient evidence to prove beyond reasonable doubt that Baumgartner had committed perjury during his naturalization proceedings. Furthermore, he criticized the majority for relying on vague and ambiguous statements made by Baumgartner years after his naturalization as proof of fraudulent intent at the time of his application. This approach, according to Justice Murphy, could potentially lead to wrongful convictions based on post hoc interpretations of past events or statements rather than concrete evidence from the time in question.