What Are Field Sobriety Tests and Are You Required to Take Them?One question I often get about Virginia DUI Law is whether people are required to take “field sobriety tests” if they get pulled over for a DUI.  It’s a good question because it leads to a lot of confusion.  So let’s first talk about what they are.

What are Field Sobriety Tests?

If you’re driving in Virginia, and law enforcement suspects you of driving drunk, they will necessarily pull you over.  Once they do, they will use Field Sobriety Tests (FSTs) to obtain further evidence that you are drunk in order to justify your arrest.  FSTs are a series of “tests,” which give the appearance that they are objective and “scientific” that law enforcement administers to you to observe for signs of intoxication. 

While every jurisdiction is a different, at least here in Northern Virginia, I see a few tests that are regularly used:

  1. Nine Step Walk & Turn (NSWT).  Under this test, law enforcement asks you to walk straight on a line, heel-to-toe for nine steps, then turn around, and do it all over again back to your starting position.  While you’re performing this test, the officer will be looking for whether you are swaying, whether you raise your arms, whether you step off the line, whether you’re able to perform the turn smoothly, whether you actually walk heel-to-toe, among other things.  The more difficulty you have performing the test, the more the officer will assert that you are drunk.
  2. One Leg Raise.  Here, the offer will ask you to stand on one leg while you raise the other leg in the air for a period of time while he counts.  Similar to the NSWT, the offer will look for lack of balance, whether you sway or raise your arms, whether you actually put your raised foot down and other indications of intoxication.
  3. Alphabet Test. While used in different forms, law enforcement will ask you to say a series of letters of the alphabet in different orders, looking for you to slur your speech, miss letters, or fail to follow directions.
  4. Horizontal Nystagmus Gaze Test (HGN). This is a test where the officer compels you to focus your eye on a particular object (such as a pen) while he or she observes your eye movement.  The officer will then move the pen left and right while you “track” the pen with your eye.  As the pen gets further away from your eyes, to the end of your peripheral vision, if your eyes demonstrate “nystagmus” or quick jerking back and forth, the officer will assert such movement demonstrates evidence of intoxication.
  5. Preliminary Breath Test (PBT).  This is a breath test taken at the scene of an arrest (at the side of the road) where the officer asks you to breath into a breathalyzer to attempt to obtain your blood alcohol level.  This test is very different from the breath or blood tests you are asked to take back at the police station (or in the hospital).  Like that test at the station or hospital, the officer will take any reading of alcohol as further evidence that you’re drunk.

What are they looking for with FSTs?

All of these tests are tools law enforcement uses to establish that you’re drunk.  More specifically, they will use these FSTs to justify that they had probable cause to arrest you for drunk driving.

The issue with these tests are the lack of “scientific” reliability to justify police action.  While the tests appear to evaluate whether you’re drunk or not, in reality, many of them (nine step walk & turn and leg raise) really test whether you have good balance.  While one person may be able to navigate these tests with ease (drunk or not) another person may have no chance without a drop of alcohol in them.

The HGN test appears to be the most “scientific” of all. The issue is the true science behind nystagmus demonstrates why it’s not helpful to determine whether someone is drunk.  Nystagmus can be caused by many different medical conditions that warrants the tester to know a person’s medical history to correlate the nystagmus with drunk driving rather than something else.  For instance, one can demonstrate nystagmus due to diabetes or high blood pressure.  But if given HGN at the scene of an arrest, they can wrongly be accused of drunk driving.

When it comes to the PBT, this test also has serious flaws.  The PBT device used can be improperly calibrated.  Also, there are substances that we consume that are not alcohol that can register as alcohol on the PBT. 

Are you required to take FSTs in Virginia?

FSTs present real issues of reliability when it comes to establishing if someone is drunk.  Fortunately, under Virginia law you are not required to take FSTs.  Indeed, you can assert your Fifth Amendment Right to remain silent, and not be compelled to undergo these tests. 

Be aware though, law enforcement has every incentive to compel you to take these FSTs.  So you should politely refuse, be calm, and don’t allow them to get you upset.  Aside from the FSTs, law enforcement will assert other behavior as evidence that you’re drunk.  Actions such as yelling, being rude, using foul language, being non-cooperative are all actions they will push as evidence of intoxication.

A special word on the Preliminary Breath Test (PBT).

One question I get about the PBT often is “James, I thought under Virginia law, I’m required to take the breath test?”  That’s a good question because the PBT is oftentimes confused with the breath test you’re compelled to take after you are arrested and taken back to the police station.  Unlike the PBT, you are civilly required to take that breath test back at the station.  If you don’t, you will be charged with civil refusal (if you’ve been charged before, the second offense is actually a separate criminal charge). 

The issue with being charged with a civil refusal is, if convicted of that civil charge, you lose your license for a year and you can’t drive at all.  In many cases I see, someone will be charged with both a DUI and civil refusal.  Because with a DUI conviction the person is eligible to get a restricted license, they will be compelled to take the DUI (even if it’s defensible) because they have to be able to drive. 

To be clear though, refusing to take a PBT is well within your constitutional right to do so.  So don’t confuse the PBT in the field with the breath test back at the station.

James S. Abrenio
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Focusing on criminal, traffic defense and personal injury cases