That's what happened on Saturday when a driver hit a bicyclist on Capitol Hill and then left the scene before police arrived. What made the case so easy for police was that the driver was using a "smart car" he'd rented from the company Car2Go.
Witnesses told police they saw one of Car2Go's small vehicles hit a bicyclist in the intersection. The driver initially stopped and even checked on the cyclist, but he then left the scene without waiting for police or handing over his identification.
While that type of incident would normally be the starting point of a lengthy police investigation, Saturday's crash wasn't tough to solve. The Car2Go vehicles, which can be rented throughout the city for 38 cents per minute, are tracked using GPS.
Car2Go workers simply found out who had rented the car involved in the crash and police did the rest. The suspect's rental was still running when officers found the damaged car.
"We went to the suspect's home and there he was, so it was quite easy," said Seattle police spokeswoman Renee Witt.
Car2Go's terms and conditions make clear the company is obligated to hand over the names of customers to the appropriate authorities.
"They are more than willing to assist us with our investigation, and we appreciate that," Witt said.
The company does give information to the police, but it also asks customers to not fess up to anything when it comes to car crashes.
In the Car2Go terms and conditions, company officials say, "In the event of an accident, the member shall not acknowledge his or her culpability, shall not accept or admit any liability."
Police say the suspect in Saturday's hit and run did follow those rules. The 28-year-old was arrested on suspicion of hit-and-run.
The bicyclist needed stitches, but is expected to be fine.
Car2Go officials did not return calls for an explanation about their policies.