Delaware Code
Subchapter XI. Miscellaneous Rules
§ 4182. Unattended motor vehicle.

(a) No person driving or in charge of a motor vehicle shall permit it to stand unattended without first stopping the engine, locking the ignition, removing the key and effectively setting the brake thereon and, when standing upon any grade, turning the front wheels to the curb or side of the highway.
(b) The requirements of subsection (a) of this section do not apply to an operator who starts the engine of a vehicle by using a remote starter or other similar device that remotely starts the vehicle's engine without placing the key in the ignition and requires the key to be placed in the ignition or physically present in the vehicle before the vehicle can be operated.