In Stokes v. United States, the U.S. Supreme Court ruled on a case involving an individual named William Stokes who was convicted of murder in New York and sentenced to death. The conviction was based largely on circumstantial evidence that he had poisoned his wife with arsenic-laced whiskey. On appeal, Stokes argued that the trial court erred by allowing hearsay testimony from a pharmacist who sold him arsenic shortly before his wife's death; this pharmacist testified about what another customer had told him regarding Stoke’s purchase of poison. The Supreme Court agreed with Stokes' argument and reversed his conviction due to improper admission of hearsay evidence at trial which violated the defendant's Sixth Amendment right to confront witnesses against him. It held that while some exceptions may exist for admitting such statements into evidence, none applied in this case because it involved testimonial hearsay rather than spontaneous exclamations or dying declarations which are typically exempted from exclusion as hearsay under common law rules.

In the dissenting opinion for Stokes v. United States, Justice Brewer argued that the defendant's right to a fair trial was violated due to improper jury instructions. He contended that the judge erred in instructing jurors they could find Stokes guilty of murder if they believed he shot his wife with intent to kill or harm her, even if she died from medical malpractice during treatment of her wounds rather than directly from the gunshot wound itself. Brewer maintained this instruction allowed for conviction based on an act not necessarily fatal by nature and thus did not meet legal definitions of murder. He also disagreed with majority’s interpretation of causation in criminal law, arguing it should be limited only to direct results of unlawful acts without intervening causes like alleged malpractice here.