Cutler: Presumed Innocent

Unlike in The Fugitive, the audience of Presumed Innocent doesn't know if the main character, Rusty Sabich, is innocent. There's evidence leading us to believe the Sabich actually killed Carolyn. When he is no longer under suspicion, he returns to his regular life until he finds the murder weapon. He confronts his wife who admits to killing Carolyn. Sabich is overcome with guilt because he knows that even though he didn't actually kill Carolyn, he is the reason why she is dead. His affair with Carolyn sparked his wife to kill her with a hammer and frame Sabich with fingerprints and sperm. Sabich was the catalyst for his wife's jealousy that caused her to viciously kill Carolyn.
Sabich's guilt is one of the most important themes in this film because he is not only guilty about Carolyn's death, but also his son's future. He knows that if he doesn't destroy the evidence that shows that his wife is the murderer, his son will live without a mother. He ends up taking an unethical approach and destroys the evidence to save himself from his own guilt. Although Sabich didn't actually kill Carolyn, through the trial and his discovery of the hammer, he feels immense guilt for her death.