Michigan DUI Field Sobriety Tests - HGN - PBT Results - Drunk Driving Trial Attorney

When a client is pulled over by the police or investigated for a DUI at the scene of accident, the police are now in evidence gathering mode.  They are looking for evidence of operation; once they have that, they are then looking for evidence of “being drunk”.  This second bucket of evidence comes from the preliminary breath tests, officer observations, statements by the defendant, and field sobriety tests.  

A lot of attorneys overlook field sobriety tests, and focus on trying to attack the chemical tests.  While it is very important to examine all of your defenses with the chemical tests, the field sobriety tests can be extremely fruitful for a motion to suppress based on an illegal arrest, or assist in a defense at trial.  

When an officer makes the decision to arrest you, it’s a combination of evidence of operation and probable cause that you committed a drunk driving offense.  An officer offers up a PBT test along with numerous field sobriety tests; most people agree to both, which is a mistake.  I’ve already discussed how to beat, and use the PBT in your favor, but field sobriety tests can also be declined.  

Taking a series of field sobriety tests is very unlikely to help your case.  The tests are usually taken at night, in potentially freezing weather with rain or snow falling, on the side of the road with other cars flying by and pressure from an authority figure.  You’re also likely tired and very nervous; it’s like trying to tie your shoes while standing in the middle of a lion’s cage.  

If you don’t take field sobriety tests, and you decline the PBT, then an officer may not have enough to make a legal arrest.  An officer will have to rely on statements about drinking, how you walked, and talked and observations of your eyes, your smells and your demeanor.  If you don’t open your mouth or make admissions then the prosecutor has a thin case for showing a valid arrest.  It’s very possible to move for suppression under these circumstances.  

If my client took field sobriety tests, it’s likely that they “failed” enough to justify an arrest; if a client happened to do very well on the tests then they can help in the argument that the officer lacked probable cause to arrest you, especially if there was not a PBT over the legal limit.  

Field sobriety tests can also assist at trial.  Each test has a set of specific instructions.  If an officer fails to read those instructions properly then the test results should be thrown out.  If an officer misrepresents how my client performed in his police report, because the video shows the client doing better than documented, it could hurt the officer’s credibility on the entire case.  

An officer is trained by the National Highway Traffic Safety Administration, and these standards are available to the public.  I use the same manual to attack the officer’s administration of the tests, and their selection of those tests.  For example, an officer is trained that there are only three field sobriety tests that have been deemed scientifically reliable to detect intoxication/impairment.  
Horizontal Gaze Nystagmus (HGN) is one of three standard field sobriety exercises conducted by law enforcement. This test looks for involuntary jerking of your eyes as you gaze toward the sides.  The other two tests are the walk-and-turn and the one-leg stand.  Any test outside of these three should NOT be used.  If an officer conducts anything else then they are conducting themselves outside of their training, and it opens the door for an attack on multiple fronts.  

Finally, if we’re working with BAC levels that straddle the 0.08 or 0.17 lines for different charges, a strong performance on the field sobriety tests can sway a jury to go with our argument that the BAC reading is inflated, and not accurate as to what it was when my client was driving the car.  Here’s an example.

My client is charged with an OWI.  He is stopped at 2 am by the police.  My client refuses the PBT, but takes field sobriety tests, which he does well on.  The officer admits to him passing most of the tests, and the video backs this up, and even discredits some of the officers observations as being too bearish.  The client has a 0.10 BAC at 3 am.  At this point we have the opportunity to argue rising blood.  

The theory goes: look how well the client did on the field sobriety tests - that doesn’t look like someone over the legal limit.  Yes he blew a 0.10 an hour later, but he had just finished drinks before getting in his car, and when driving he was below 0.08, and it only rose to 0.10 after time has passed.  This technique requires some well planned cross-examination of the police officers, and potentially the Michigan State Police representative or an expert witness brought in by the defense. ​