What doctrine relates to the ability of law enforcement to search a moving vehicle without a warrant?

The appropriate doctrine that pertains to law enforcement's ability to search a moving vehicle without a warrant is indeed the Mobility Doctrine. This principle is grounded in the understanding that vehicles are inherently mobile, which means they can easily be moved out of the jurisdiction of law enforcement. This characteristic of vehicles creates a special circumstance where the exigency of the situation allows officers to conduct searches without the need for a warrant.

The Mobility Doctrine is part of a broader legal framework that acknowledges the practical realities law enforcement faces during traffic stops or when dealing with vehicles on the road. The rationale is that if officers had to wait to obtain a warrant, often a vehicle could be driven away or evidence could be lost. Therefore, as long as officers have probable cause to believe that evidence of a crime is in the vehicle, they can conduct a search on-the-spot.

This doctrine does not negate the need for probable cause; rather, it highlights how the unique attributes of a vehicle change the legal standards that apply to searches in such situations.