In McDowell v. United States, the Supreme Court ruled on a case involving an individual who was convicted of perjury after testifying in a court martial proceeding. The defendant, McDowell, argued that he could not be charged with perjury because the court martial did not have jurisdiction over him as he had been discharged from military service prior to his testimony. However, the Supreme Court disagreed and upheld his conviction. They reasoned that even if the court martial lacked jurisdiction over him personally due to his discharge status at the time of testimony, it still held general authority to conduct proceedings and hear evidence related to its cases. Therefore, false statements made under oath during such proceedings constituted perjury regardless of personal jurisdictional issues.

In the dissenting opinion for McDowell v. United States, Justice Brewer argued that the defendant's constitutional rights were violated due to an improper jury instruction. He contended that it was incorrect for the trial judge to instruct jurors they could find McDowell guilty based on his failure to testify in his own defense. This, according to Justice Brewer, infringed upon McDowell's Fifth Amendment right against self-incrimination and fundamentally undermined a cornerstone of American jurisprudence: that individuals are presumed innocent until proven guilty beyond reasonable doubt. The burden of proof should always rest with the prosecution and not be shifted onto defendants by implying their silence is indicative of guilt. Therefore, he believed this case warranted reversal and remand for a new trial respecting these principles.