What makes a police officer disregard his oath and cross the Thin Blue Line. Some say that it may be caused by the stress of the job. While others say that they are just criminals themselves. We will take a look at four police officers, Richard Crafts, Drew Peterson, Lawrencia "Laurie" Bembenek, and Gerard Schaefer. We will try to figure out what caused them to murder and cross that Thin Blue Line.