how could tom robinson be viewed as a scapegoat

Tom Robinson is convicted of the rape of Mayella for no other reason than he was black. He was convicted because of prejudice against the color of his skin....... he was the scapegoat because Mayella's father should have been prosected for beating her, and both Mayella and her father should have beem prodecuted for lying about everything...... but they weren't. Tom, innocent as he was, became the scapegoat for everyone's trangressions.