The smiley face murder theory is a theory advanced by retired New York City detectives Kevin Gannon and Anthony Duarte, as well as Dr. Lee Gilbertson, a criminal justice professor and gang expert at St. Cloud State University. It alleges that 45 young men found dead in bodies of water across several Midwestern American states from the late 1990s to the 2010s did not accidentally drown, as concluded by law enforcement agencies, but were victims of one or multiple serial killers.