BRISTOL, R.I.  Betty Anne Waters still greets her lunch customers here as they tuck into pints of Guinness and Reuben sandwiches at Aidan’s, a pub hard by the harbor in this small, boat-building town.

Ms. Waters had only a job as a waitress, her high school equivalency, two kids and a stack of bills when she set out to rescue her brother Kenneth Waters, who served 18 years in prison for a murder he did not commit. Now she has a college degree, a law degree and the stunning achievement of having succeeded, after nearly two decades, in overturning her brother’s conviction.

But after he was released in 2001  and the flurry of news attention faded  Ms. Waters, 56, returned to Aidan’s, to the simple life of tending to her family and the pub where she is now general manager. No law firm. No fat salary. No fame.

“As I got to know her, I understood it,” said Barry Scheck, a lawyer who assisted her on the case. “She did not become a lawyer to be a lawyer. She became a lawyer to get her brother out of jail.”