HILARY SWANK continues to prove to be an actor who saves herself for the weightiest and most willful roles (see: Million Dollar Baby, Boys Don't Cry, Amelia, The Core... wait, forget about that last one) with Conviction. Here she plays Betty Anne Waters, a woman who dropped out of high school only to go back for her GED, then a college degree, and finally a law degree—solely in order to represent her brother, who was wrongfully sentenced to life in prison for the brutal murder of an elderly woman.

Based rather faithfully on the true story, Conviction sheds light on the Innocence Project, the litigation organization dedicated to using DNA technology to overturn wrongful sentences that were doled out prior to its development. In the case of Kenny Waters (Sam Rockwell), his eventual freedom would have been thwarted had the state of Massachusetts legalized the death penalty, and without the persistence of his sister, any further legal pursuits through the public defense system would never have been carried out. His case levels serious, if familiar, charges against the efficacy of a classist justice system.

Conviction nimbly depicts its subjects, drawing us into a sibling bond cemented by troubled, rowdy childhoods marked by abandonment and separation. For much of the film Betty appears blinded with determination, and while we sympathize with her quest, we also hear the voice of reason when her best friend Abra (Minnie Driver) cautions that the truth may not be on her side. Even Kenny, as prone to violent temper as he is charming, seems to believe in his own cosmic guilt.

This film is a rough and unlovely ride (thanks in part to Juliette Lewis' small but memorable role as an alcohol-ridden ex-girlfriend with spectacularly bad teeth), but its ultimately rewarding story doesn't for a moment release you from its grip.