A more thorough explanation:

DRE

DRE stands for Drug Recognition Expert. A DRE is a law enforcement officer who is trained to recognize signs of drug impairment in drivers.

For example, if a driver is pulled over and suspected of driving under the influence of drugs, a DRE may be called to the scene to conduct a series of tests to determine if the driver is impaired. These tests may include checking the driver's pulse, blood pressure, and body temperature, as well as conducting a series of eye exams and balance tests.

Another example of when a DRE may be used is during a DUI checkpoint. If a driver is suspected of being impaired, they may be asked to pull over to a separate area where a DRE can conduct a more thorough evaluation.

A DRE is a highly trained law enforcement officer who specializes in identifying drug-impaired drivers. They use a variety of tests and evaluations to determine if a driver is under the influence of drugs. The examples provided illustrate how a DRE may be used in different situations to identify and apprehend drug-impaired drivers.