Despite claims to the contrary, no evidence has yet been found to suggest that Thomas Jefferson habitually smoked tobacco, hemp, or any other substance. None of his own papers make any reference to a smoking habit, nor do any known family letters, visitor accounts, or early biographies.
The only known references to Jefferson smoking at all is in the context of diplomatic meetings with representatives of American Indian tribes. Jefferson recorded the proceedings of a conference with leaders of the Wabash and Illinois tribes in 1793: "Three-legs, a Piankishaw chief, came forward and carried round a white pipe from which every one smoked." Jefferson was also reportedly at several other such ceremonies where calumet pipes were smoked. He also wrote in 1796 to Jean-Baptiste Ducoigne, a chief of the Kaskaskia tribe, "Perhaps I may come some day yet and smoke the pipe of friendship with you and your friends."