In the 1892 case of Clyde Mattox v. United States, the U.S Supreme Court ruled on an issue related to jury misconduct. The defendant, Clyde Mattox, was convicted for murder in a lower court and appealed his conviction based on alleged juror misconduct during deliberations. Specifically, it was claimed that jurors had read newspaper articles about the crime which were not presented as evidence at trial. The Supreme Court held that if a juror looks beyond the courtroom for information regarding a case they are deciding upon - such as reading news reports or conducting independent investigations - this constitutes misconduct and can serve as grounds for overturning a verdict due to potential prejudice against the defendant's right to fair trial. Therefore, even though there wasn't direct proof showing that these actions influenced their decision-making process negatively towards Mattox; given its potential impact on impartiality required from jurors while making decisions; it warranted reversal of his conviction.

In the dissenting opinion for Clyde Mattox v. United States, Justice Brewer argued that the defendant's Sixth Amendment right to a fair trial was violated because of an improper jury instruction given by the trial judge. The judge had instructed jurors they could consider statements made by a deceased person who was not available for cross-examination at trial. According to Justice Brewer, this denied Mattox his constitutional right to confront witnesses against him and challenge their credibility through cross-examination. He believed that allowing such hearsay evidence undermined the integrity of criminal trials and set a dangerous precedent which threatened defendants' rights in future cases.