Stevenson’s book details multiple cases and clients he works with, but McMillian’s story is carried throughout the entire memoir which is why Cretton decided to keep it at the center of the movie Just Mercy . “I felt like the trajectory of that story really paints a clear picture as to how this justice system that we have in our country is really working for the rich and powerful and not really working for the poor,” Cretton explained. “It really highlights the different aspects of how difficult it is for this system to admit that [it has done] something wrong even when all the evidence is pointing towards that.”