A common misconception is that if you, as a driver, pass the Breathalyzer test, you will not be arrested or convicted of driving under the influence. This is far from the truth. Many DUI convictions have come about because of evidence provided by dash cam video, field sobriety tests, police officers notes, official reports and the testimony of police officers in courts.
The Breathalyzer has been around since 1954. The results of countless Breathalyzer tests have resulted in many a DUI conviction. On the other side of the coin though, many a defense attorney have had the results of a Breathalyzer test thrown out because of improper administration of the test, improper calibration of the Breathalyzer machine and improper training of the person administering the test.
Breathalyzers work on the concept that alcohol content of the breath can correlate to alcohol content of the blood (BAC). This measurement is determined by having the subject give a breath sample through a mouthpiece. The sample is then passed through chemical reagents. The resulting chemical reaction is the measured by the Breathalyzer to give an approximate blood alcohol content (BAC). Many variables can affect the final reading. The Breathalyzer is calibrated for the average man so a smaller man or a woman can have a higher reading. Things such as diet, medications and weather conditions can also have an effect on the outcome. Variables such as operator training or lack of, machine calibration and location, such as was the machine brought out in the field or is it in a fixed location, all have a bearing on the outcome of the Breathalyzer test.
Even if you take the Breathalyzer test and the results were less than the legal limit of 0.08%, you still may be arrested, tried and convicted of DUI.
Field Sobriety Tests
One tool a police officer uses is field sobriety tests. The police officers observations of how you do during a field sobriety test are usually backed up with dash cam video of the test, the officer’s official police report of the incident and the officers field notes. These will, during your trial, be backed up by the officer’s sworn testimony in court.
A well trained officer will be consistent in their administration of field sobriety tests. One of the first things a well trained officer will ask you before administering a field sobriety test is if you have any preexisting conditions or injuries that might affect the test. If you have any type of medical condition or on any prescription medication, be sure to tell the officer. This can affect the outcome. Remember, even if the officer does not make note of this, your answer is most likely being videotaped along with audio. If you do indicate to the officer that you have a physical disability or a medical condition, the officer will most likely substitute some type of verbal test.
Before administering a field sobriety test, a well trained police officer will scan the area for any uneven surfaces or other hazards. Potholes, dips and gravel can all adversely affect the test.
Before administering a field sobriety test, the officer will demonstrate to you what he wants done. The officer should tell you to stand in place and watch while he demonstrates the test. Remember, this is part of the test. You are being observed to see if you can follow instructions. If you begin the test before the officer is done demonstrating the test and you are instructed to begin the test, this could be interpreted as impairment.
Of course, the best way to avoid a DUI is not to drink and drive.