The **Authority** has the power to **immobilize the vehicle** of a driver who has tested positive for alcohol or drugs. This is because driving under the influence of these substances is a very serious offense, with consequences such as fines, loss of driving license points, and even the possibility of going to jail if the lives of others are endangered.

However, the vehicle does not have to remain immobilized if there is **another driver available** who can take charge of the vehicle. This means that if there is a person who has not consumed alcohol or drugs and can drive, this person is allowed to replace the drunk driver, thus avoiding the immobilization of the vehicle.

In summary, the immobilization of the vehicle is a preventive measure to prevent a person under the influence of alcohol or drugs from continuing to drive, but it can be avoided if an alternative driver is available.