A more thorough explanation:

Definition: A drug-recognition expert is a person who has received specialized training to identify different types of drugs and alcohol, understand their effects on the human body, and recognize the signs and symptoms of drug and alcohol intoxication. They are often abbreviated as DRE.

Example: A police officer who suspects that a driver is under the influence of drugs or alcohol may call in a drug-recognition expert to assess the situation. The DRE will conduct a series of tests to determine whether the driver is impaired and, if so, what type of substance they may have consumed.

Explanation: The example illustrates how a drug-recognition expert may be called upon to assist law enforcement in identifying and assessing cases of drug or alcohol intoxication. By using their specialized training and knowledge, DREs can help determine whether a person is impaired and what type of substance they may have consumed, which can be crucial information in legal proceedings.