Harris v. Johnston was a case heard by the United States Supreme Court in 1806. The dispute arose when William Harris, an attorney from Virginia, sued John Johnston for failing to pay him $1,000 as compensation for legal services rendered. In his defense, Johnston argued that he had already paid Harris and thus did not owe any additional money. After hearing arguments from both sides of the dispute, the court ruled in favor of Harris and ordered Johnston to pay him $1,000 plus interest on the amount owed since it had been outstanding for some time. This decision established that attorneys were entitled to receive payment for their services regardless of whether or not they had received prior payments from their clients; furthermore it set a precedent which has been followed ever since with regards to compensating lawyers who provide professional services within the scope of their practice area.

In Harris v. Johnston, the Supreme Court was asked to decide whether a state court had jurisdiction over a case involving citizens of different states. The majority opinion held that it did not have such jurisdiction because the Constitution only grants federal courts this power. Justice Samuel Chase dissented from this decision and argued that under the Judiciary Act of 1789, state courts were given concurrent jurisdiction with federal courts in cases between citizens of different states. He further argued that if Congress intended for these matters to be exclusively within the purview of federal courts, they would have explicitly stated so in their legislation rather than leaving it open to interpretation by judges or other government officials. Ultimately, he concluded that since there was no clear indication either way as to which court should hear such cases, both state and federal tribunals should be allowed to do so until Congress clarified its intent on this matter through additional legislation or amendment of existing laws.