Police watch client’s vehicle come to stop at intersection and then proceed. Short distance later car stops and driver and passenger get out of vehicle and switch positions. Police stop car based on this “suspicious” activity. Client/Driver, now in passenger seat admits to drinking and performs less than perfect on field sobriety tests. Arrest follows. Defense prepared to argue that stop of vehicle was without reasonable cause and defendant’s pre-existing medical conditions made him unsuitable candidate for field sobriety tests. DWI charge dismissed prior to trial.