“Rarely, accidental deaths occur when a car is started and left running in a garage to warm up while the driver goes back to the house. Carbon monoxide from the exhaust then leaks into the house, killing the residents. Occasionally, someone commits suicide in a garage by leaving the car running, and at the same time inadvertently kills the occupants of the house as well.” – Dominick J. Di Maio & Vincent J. M. Di Maio, Forensic Pathology