Robert Redford doesn’t shy away from films with a powerful political thrust. Recall All the President’s Men, Three Days of the Condor and even The Way We Were, in which Communist paranoia splits apart Katie and Hubbell, arguably the coolest couple in cinematic history.

In The Conspirator, opening nationwide on April 15, Redford reaches back to the U.S. Civil War for his latest project as director. Released in conjunction with the 150th anniversary of the start of the war on April 12, the movie reveals some disturbing flaws in the justice system that surfaced after Abraham Lincoln’s assassination and that parallel today’s problems. The movie stars Robin Wright as Mary Surratt, the owner of the boarding house on High Street in Washington where John Wilkes Booth lived. Based on flimsy evidence, she is charged with conspiring to murder Lincoln, along with her son, a Confederate soldier who fled to Canada after Lincoln’s death.