The PAS requires a certain amount of breath pressure before it will capture a sample of breath suitable for a BAC result. Many folks have physical limitations or breathing problems that limit their ability to perform. For example, if a person is suffer from Long Covid they can have lung scarring that may prevent them from providing sufficient breath pressure to obtain a result on the preliminary alcohol screening device.
Second, people with physical disabilities may not be able to perform SFST exercises. Long Covid patients again may have problems. Some officers may ask if the subject has medical problems but not actually “dig in” and inquire whether they may be suffering from Long Covid.
There is a real danger of cops making incorrect arrest decisions on drivers showing signs of fatigue, shortness of breath and other symptoms of Long Covid. These objective symptoms can be confused with alcohol and/or drug impairment.
Most DUI Attorneys will or should inquire whether the client is afflicted with certain medical conditions that can create possible issues in the defense of DWI.
Regarding SFST exercises, only the HGN requires the officer to perform a “medical assessment”. Other FSTs such as the Walk and Turn and One Leg Stand do not require a medical assessment phase. Therefore, common physical ailments can often mimic signs of impairment.