Pierson v. Post was a court case in the United States in 1805. It was the first time the Supreme Court decided a case involving a fox hunt. In the case, Jesse Pierson said that Otis Post had "unlawfully, wilfully and maliciously" taken a fox that Pierson had been chasing on his property. Otis Post argued that he had a legal right to take the fox because it was on Pierson's property.
In the end, the Supreme Court decided that Pierson had the legal right to keep the fox. They said that Post had no right to take the fox away because it was on Pierson's property. The ruling set an important legal precedent - it showed that when someone is hunting on their own property, they have the right to keep what they find.