I read that they were able to locate the remains of the body because of GPS system in stolen Jeep. Wouldn't he have driven the Jeep into the town or does the GPS record past locations?
Without knowing what type of GPS it was, or how the system was setup, the best I can do with this kind of question is to reference my own GPS system. Mine is a fairly simple Magellan handheld. As long as mine is turned on, and isn't set to backtrack, it's going to log every location I've been to - it logs the route I've been following - that way, I can save the route, and follow it back out. Assuming the one in the Jeep worked in the same fashion, it was just a matter of them saving the route, and following it back.