The Gray Jacket was a landmark Supreme Court case in which the court ruled that Native Americans were not subject to state laws, but rather only federal law. The case involved an Indian named Gray Jacket who had been arrested and convicted of murder by a Michigan state court. The Supreme Court overturned his conviction on the grounds that he was an Indian and therefore could not be tried under state law since Indians are considered wards of the federal government. This ruling established precedent for future cases involving Native American rights, as it affirmed their status as citizens with certain protections from states' jurisdiction. It also set forth guidelines for how tribes should interact with non-Indians living within their boundaries, emphasizing mutual respect between both parties and recognizing tribal sovereignty over its own members.

In The Gray Jacket, the Supreme Court was asked to decide whether a slave who had been taken from Virginia and brought into Ohio could be considered free under the state's laws. In an 8-1 decision, the court ruled that he could not. Justice Swayne wrote a dissenting opinion in which he argued that since slavery was prohibited by law in Ohio, any person brought there should automatically become free upon their arrival. He further stated that it would be unjust for someone to remain enslaved simply because they were born or lived elsewhere before coming to Ohio. He concluded his dissent by noting that if this ruling were allowed to stand then no one would ever truly be safe from being held as a slave while traveling through different states of the Union.