Also a favorite of the California Highway Patrol, the test subject is told to stand with his or her left hand held at waist level, palm facing up. They are told to place the right hand into the palm of the left hand, with the right palm facing down. When told to begin, the test subject is instructed to rotate the right hand (palm up and down) while clapping into the palm of the left hand. The subject is instructed to count "one, two, one, two, etc."
As the test begins, the officer will bark orders for the subject to increase the clapping speed.
If the subject does not increase the speed to the liking of the officer, if the right hand rolls or does not completely rotate, or if the subject does not count out loud, the test is a failure.