8.) James Wren
James Wren told his accomplice in 2008 that he was joining the Phoenix Police Department and was "down to do shit." The pair set up drug deals that ended with Wren stopping suspects in his patrol car and stealing tens of thousands of dollars. He'd earned $36,000 for himself after two such robberies before members of his own force arrested him -- at some risk to themselves -- at the Estrella Mountain Precinct. He was sentenced in 2011 to 1.5 years in prison.
7. Martin Ward
Martin Ward was a Tucson cop for five years before an investigation accused him of forging documents to receive government benefits, threatening his girlfriend and assault. That's bad enough -- but Ward's a sicko who enjoys downloading and sharing child porn. In 2013, while being sentenced to 10 years in prison, Ward told his former employer: "To the Tucson Police Department -- the next time you want to take a shot at me behind my back, aim at my head."