Anyone know whom this movie was really about?

I usually research these "true story" movies after I watch them to get the true story behind the "true story"....if that makes sense. It's often not hard to find, but this one really has been difficult. If anyone can help, I'd really appreciate the information. The movie is good, but there HAS to be something missing. I'm very curious to find out why she was convicted with almost no evidence (as the movie portrays the story). Thank you!