JUST MERCY.

• Author: Slade, Stephanie

Fairly early in Just Mercy, an employee of the Monroeville, Alabama, district attorney's office encourages a young lawyer played by Michael B. Jordan to visit the nearby To Kill a Mockingbird museum. It's housed in the courthouse where Harper Lee's father worked, the assistant explains; you can see the place where Atticus Finch once stood. The sly joke, of course, is that Finch is a fictional character.

Not so with this movie's protagonist. Bryan Stevenson really is a Harvard Law graduate who moved to the Deep South in 1989 to represent impoverished death row inmates. He really did found a practice called the Equal Justice Initiative, which has won relief for hundreds of wrongly convicted and...