The word patsy as meaning "someone who is blamed for a crime" originated in US slang in the 1870s, and there are a lot of different theories about the etymology of that term. It's a possibility is that it could be from the Italian word pazzo, which meant "madman", but that's pretty loosely supported. One hint is that the earliest spellings of patsy were with a capital first letter, which implies that it's a name. It might come from the Irish diminutive of Patrick, Paddy, which was considered a stereotypical immigrant name at the time. It could also come from Patsy Bolivar, a character in vaudevillian skits who was always blamed by the other schoolboys for classroom pranks (the actors' traveling could have helped it spread around the country). The word really only got popularized in the early 1900s, eventually peaking in usage in the 1970s.
Adam Aleksic, a rising sophomore studying linguistics and government at Harvard University, has been described as the internet's sixth most famous etymologist. He also has disturbing interests in politics, vexillology, geography, board games, conlanging, and law.