Clients frequently have questions about roadside sobriety tests and their relevance in a DWI prosecution. Roadside sobriety tests became widely used by police in the late 1970s because of the general inability of officers to determine impairment without a blood or breath alcohol reading. At that time, breath alcohol measuring devices were not widely used.

Social scientists conducted studies and settled on a battery of three so-called standardized field sobriety tests (“SFSTs”). The theory is that the statistical results of these studies can be relied upon so long as the SFSTs are administered precisely the same way as the initial scientific studies. To assure that the tests are administered, scored, and demonstrated in a standardized fashion, police officers who use SFSTs must take a training course conducted by the New Jersey State Police. If an officer is not certified in the use of SFSTs, that officer may still testify in court, but the weight of their conclusions is greatly diminished. SFST police certification is something we always seek during the defense of our clients.

The three SFSTs currently used in New Jersey are the Horizontal Gaze Nystagmus Test (“HGN”), the One Leg Stand Test (“OLS”) and the Walk and Turn Test (“WAT”). Each test must be scored and demonstrated in a precise fashion consistent with the SFST training the officer has received. Let’s discuss each test.

Horizontal Gaze Nystagmus

The Horizontal Gaze Nystagmus Test is not yet accepted in New Jersey courts as a reliable indicator of intoxication. The test is an attempt to determine if a defendant has an involuntary twitching of their eyes. This twitching is called a nystagmus. Alcohol consumption can cause a nystagmus. The reason the test is not widely accepted under New Jersey law is because there are 256 other medical reasons why a defendant could have a nystagmus unrelated to alcohol consumption. We frequently see police officers inappropriately administering this test. An experienced analysis of the roadside video can reveal these problems: For instance, the entire test cannot be completed properly in under 86 seconds. We frequently see police officers cutting corners on this test.

One Leg Stand Test

The One Leg Stand Test requires a defendant to stand on the leg of their choice with the other leg elevated approximately 6 inches of the ground. The defendant is asked to count from 1 to 30 with their arms at their side. The officer is trained to look for four specific “clues” which include: putting the foot down, using arms for balance, swaying while balancing, and hopping. A defendant fails the test if they exhibit two or more of these “clues”.

Walk and Turn Test

The Walk and Turn Test requires a defendant to first stand in an “instructional pose” with their right foot in front of their left, in a heel-to-toe fashion and arms at their side. Although a defendant may believe they are only being given instruction at this point, the instructional pose is actually the first part of the Walk and Turn Test. The remainder of the test requires the defendant to walk in a heel-to-toe fashion, in a straight line, for 9 steps. The defendant is then required to complete a turn and perform the same 9 heel to toe steps in a return direction. The officer is trained to look for 8 specific clues, which include: starting too soon, cannot keep balance while listening to instructions, stopping while walking, not touching heel-to-toe, stepping off the line, using arms for balance, improper turn, and incorrect number of steps. If a defendant exhibits 2 or more clues, they have failed the test in the eyes of the police.

Traditionally, a police officer will testify in a DWI trial that a defendant exhibited 2 or more clues for each of the SFSTs and that that failure supports a conclusion of intoxication.

Even without a breath alcohol reading, a New Jersey judge can convict a defendant of DWI simply based solely on the failure to adequately perform SFSTs.

Do you have to perform the balance tests for the police officer?

The answer is no. Unlike the legal requirements to provide breath samples if arrested, you have no obligation to perform roadside sobriety tests. Most police officers will have a defendant exit the vehicle and tell them they are going to run them through a series of balance tests “to make sure they are okay to drive.” The officer is actually starting the process of building a case against you. New Jersey law allows a conviction against a defendant if he fails roadside. No breath reading is necessary.

Since you have no obligation to perform the balance tests, you probably should not do them if you have had anything to drink. You are likely going to be arrested if you are asked to exit the vehicle, so performing the balance tests only hurts your defense. You may have a very strong DWI defense if there are no balance tests and we find a technical problem with the breath alcohol machine. In those cases, the prosecutor has little ability to prove a DWI beyond a reasonable doubt.

Are there conditions other than alcohol consumption which can cause you to fail the roadside balance tests?

Absolutely. When officers receive balance test training, they are told that certain conditions will weaken the use of the balance tests as an indicator of intoxication. Specifically, defendants with inner ear infections may have balance problems. Defendants who have a heeled shoe in excess of 2” will also have problems performing the SFSTs. Finally, defendants over 65 years old will have a diminished ability to perform balance tests. If any of these factors are present in your case, you have a strong defense to the balance test results since these conditions significantly diminish the probative value of balance testing in proving a DWI beyond a reasonable doubt.