Defendant had a head-on collision with injuries to both parties. He was given field sobriety tests on the scene of the collision and did not perform well on those tests with the exception of the Horizontal Gaze Nystagmus (HGN) test where he showed no signs of impairment from any central nervous system depressant. He admitted to having consumed prescription medications though the officer did not ask him when he had consumed them. The officer placed him under arrest with the assumption that he was under the influence of some drug other than a CNS depressant. A blood test was performed which came back with the presence of only Xanax/Alprazolam which is a central nervous system depressant. By virtue of the perfect HGN test which would have shown signs of CNS depressant impairment if it existed, we were able to show the court that the substance in his blood did not cause any of the other signs of impairment or poor vehicle operation. He was found not guilty of DWI.