If you are pulled over and the police suspect you of driving under the influence, they will request you to perform a field sobriety test. Common tests include walking a line in a heel-toe manner, standing on one foot while counting, and an eye nystagmus test which examines for erratic eye movements. These tests are designed, and the police request you to perform them, in order to establish probable cause to arrest you for driving under the influence.
We all know that driving under the influence of alcohol or drugs is never a good idea. Not only is it illegal, but it has the potential to endanger the lives of yourself, your passengers, other people on the road and pedestrians.
If a driver is impaired by drugs or alcohol when he or she is operating a vehicle, it is against the law. This is because they are at a much higher risk of making an error of judgment, are subject to delayed reaction times and are more likely to engage in reckless or distracted driving. In order to enforce this law, drivers may be stopped and asked to take a Breathalyzer test, which can determine the level of alcohol in their blood.