Becky's father and the county Judge, who is based in Constantinople. He is the most revered figure in St. Petersburg. He takes a fondness to Tom after he leads Becky out of the cave, hoping he'll become a lawyer, which indicates the fallibility of the lawman, who should be more wary of mischievous Tom.
The timeline below shows where the character Judge Thatcher appears in The Adventures of Tom Sawyer. The colored dots and icons indicate which themes are associated with that appearance.
...don't pay attention, whispering and teasing one another. Lawyer Thatcher arrives along with the dignified Judge Thatcher , his wife, and his daughter – Tom's crush. The children and their instructors are... (full context)