In the United States v. Buchanan case of 1913, the Supreme Court ruled on a matter concerning federal jurisdiction over crimes committed in unincorporated territories. The defendant, Buchanan, was charged with manslaughter in Alaska before it became an incorporated territory of the U.S., and he argued that his trial should have been held under common law rather than federal law. However, the court disagreed and upheld his conviction by ruling that Congress had full legislative power over unincorporated territories like Alaska at that time. Therefore, even though Alaska did not yet enjoy all constitutional protections as an incorporated territory would have done so; its laws were still subject to Congressional legislation which included application of federal criminal statutes such as those under which Buchanan was convicted.

In the dissenting opinion for United States v. Buchanan, it was argued that the defendant's conviction should be overturned due to a lack of evidence proving his guilt beyond reasonable doubt. The justice believed that there were significant inconsistencies in the prosecution's case and highlighted several instances where key witnesses provided contradictory testimony. Furthermore, he expressed concern over potential bias from jury members who may have been influenced by public sentiment against Buchanan rather than focusing solely on the facts presented during trial. He also criticized what he saw as an overly broad interpretation of conspiracy laws used to secure Buchanan’s conviction, arguing this could set a dangerous precedent for future cases. Ultimately, while acknowledging serious allegations against Buchanan, he maintained that these issues raised enough doubt about his guilt to warrant acquittal or at least a new trial.