Dave Dahl, the founder of Dave's Killer Bread, was in prison for a total of about 15 years due to various offenses including drug distribution, burglary, armed robbery, and assault. He started using drugs and dropped out of high school, which led to a life of petty crime and multiple incarcerations. Dahl was in and out of prisons around the US for these offenses. He also struggled with addiction and mental health issues during this time. His journey included drug addiction, criminal activity, and several jail terms before he turned his life around after his last prison release in 2004, eventually creating the successful Dave's Killer Bread brand.