Field Sobriety Tests in Washington State

The term “field sobriety tests'' is a misnomer. According to the most recent research, even state of the art field sobriety tests (FSTs) currently approved by the Federal Government do not measure impairment of the ability to safely drive a car. Rather, they measure agility and the ability to do certain physical feats under extreme pressure. Calling them “roadside agility tests” is more accurate, but most people know them as field sobriety tests.

What Happens if You Refuse to Take a Field Sobriety Test?

Field sobriety tests are not mandatory and there is no legal obligation to submit to the tests under Washington Law. However, refusing the tests will probably not prevent the driver’s arrest and may even make the arrest happen more quickly. A refusal to do the tests will undoubtedly make the officer more suspicious. Prosecutors like to argue that the refusal to take field sobriety tests is evidence of “consciousness of guilt,” but there are many good reasons why a person might refuse to take the field tests.

A driver who refuses to take the sobriety tests forces the officer to make the decision to arrest based upon the evidence of intoxication, if any, the officer has obtained up to the point the FSTs were refused. If the officer smelled alcohol on the driver’s breath, and noticed ANY other signs that might indicate intoxication, the arrest is almost a certainty if the driver refuses the field tests.

The arrest might have been avoided had the driver taken the tests and passed them 100%. On the other hand, for most officers, less than perfect performance on the field sobriety tests will likely constitute a “failing” grade and result in an arrest anyway. The driver being asked to take field sobriety tests faces a difficult decision, and one that must be made quickly as the officer awaits an answer to his question.

Field Sobriety Tests Approved by the National Highway Traffic Safety Administration

Only three types of FSTs are approved by the Federal Government (National Highway Traffic Safety Administration or NHTSA) for use by police: Horizontal Gaze Nystagmus (HGN), the “One-Leg Stand” and the “Walk and Turn” tests. These are the ONLY tests the federal government has determined are “empirically related” to blood alcohol levels. To be valid, the NHTSA approved tests must be administered and graded precisely according to NHTSA rules for each and every DUI suspect. Let’s examine the approved sobriety tests:


The Horizontal Nystagmus Test is an eye test. During this test, the officer tries to estimate in degrees where the suspect's eye bounces when following a pen or finger from side to side. The vast majority of Washington courts have ruled that this test is not reliable enough to be used as courtroom forensic evidence that a driver was intoxicated. Still, many police officers think it is the most accurate field sobriety test.

One-Leg Stand

During the one-leg stand test, the subject stands on one leg for approximately 30 seconds. NHTSA instructs the officer to look for four clues to determine pass or fail:

  • Sways while balancing
  • Uses arms to balance
  • Hops
  • Puts foot down

According to NHTSA, the best that can be said about this test is that if the individual is unable to finish the test, the probability of correctly identifying an individual with a blood alcohol concentration of .08% or higher is 65%. This means that under ideal conditions, this test fails 35 out of 100 people whose blood alcohol concentration is not over the legal limit.

Walk and Turn or Walk the Line Test

The federal procedure for this test requires a visible line to walk or a straight reference point, like a curb, in plain sight. Further, the testing surface must be level. NHTSA requires the officer to give specific instructions, including requiring the suspect to stand in a “heel to toe” position during the instructions. Next, the suspect must walk nine steps up and nine back, all heel to toe, all on the line. Here are the clues used to determine pass or fail:

  • Can’t balance during instructions
  • Starts too soon
  • Stops while walking
  • Doesn’t touch heel to toe
  • Steps off the line
  • Uses arms to balance
  • Loses balance on turn or turns incorrectly
  • Takes the wrong number of steps

If the individual is unable to complete the heel to toe test, the probability of correctly classifying an individual as having a .08% BAC or more is 68%. This means that 32 of every 100 people who fail this test are, by NHTSA logic, “legally sober.”

Other Common Field Sobriety Tests

Experienced DUI defense attorneys have heard officers testify about a variety of “sobriety tests” which are offered to prove that a driver is drunk. The below field sobriety tests are not scientific measures of intoxication — and there is no research to justify use of such tests:

Coin Pickup Test

During the coin pickup test, an officer drops coins on the ground. Driver tries to pick them up. Driver has trouble picking one or more of them up, or misses one in the darkness.

Hand Pat Test

With the hand pat test, the officer tells the driver to pat their hands in a particular sequential order: up, up, up and down, down, for instance. If the driver fails to follow instructions, (because she has never tried such a thing before) it’s a “fail.”

Trick Questions

An example of a trick question is: “What was the date of your thirteenth birthday?” If not answered properly, this shows the driver is under the influence of alcohol.

Partial ABCs

Partial ABCs is another common field sobriety test. Say the abc’s from “D” through “U,” without singing them. If not said properly — or if done the way they were learned (by singing them) — you’re one step closer to jail.

Tongue Twisters

An officer may ask you to do tongue twisters. For example, say“sophisticated statistics” or “Methodist methods” quickly three times.

Time Estimates

Time estimates are a common type of field sobriety test. The officer may tell you to close your eyes and estimate when 25 seconds has elapsed.

Contact a Knowledgeable Washington DUI Attorney

Whether you took a field sobriety test or refused it, an experienced DUI attorney can help to fight the charges that have been brought against you. Providing comprehensive counsel and adept advocacy, the Fox Law Firm PLLC has been successfully representing clients throughout Washington in DUI cases since 1985. Contact Jon Fox for a complimentary consultation by calling (425) 274-9190.