If used legally, driving while under the influence of marijuana is:

Driving while under the influence of marijuana is illegal because it impairs a person's ability to operate a vehicle safely. Just like alcohol, marijuana affects coordination, reaction time, and judgment, all of which are critical for safe driving. Laws regarding driving under the influence are strict to ensure the safety of all road users. In Washington State, laws are in place to penalize individuals who drive impaired due to any substances, including marijuana, reinforcing that it is not only dangerous but also against the law. This helps to promote responsible behavior and maintain public safety on the roads.