The “One-Leg Stand Test” in DUI Cases – How It Works

The one-leg stand test is a standardized field sobriety test (SFST) that police administer during traffic stops to determine whether you are under the influence of alcohol or drugs.

For the one-leg stand test, the officer instructs you to stand with one foot about six inches off the ground and count aloud by thousands (one-thousand-one, one thousand-two, etc.) for 30 seconds. If you

• sway,
• use your arms to balance,
• hop, and/or
• put your foot down,

the police can use that as evidence you may have an illegal blood alcohol concentration.

In this article, our California DUI attorneys discuss:

• 1. Instructions
• 2. The 4 Clues
• 3. Reliability
• 4. Other Field Sobriety Tests
• Frequently-Asked-Questions
• Additional Resources

1. Instructions

Below are the one-leg stand test instructions given by the National Highway Traffic Safety Administration (NHTSA) to DUI law enforcement officers on how to administer the one-leg stand sobriety test:

STEP 1

Provide the DUI suspect the instructions listed below and from a position of interrogation (that is, with your weapon away from the suspect):

STEP 2

Say: STAND WITH YOUR HEELS TOGETHER AND YOUR ARMS DOWN AT YOUR SIDES LIKE THIS

• Demonstrate how you want the suspect to stand.

STEP 3

Say: WHEN I TELL YOU, RAISE ONE LEG ABOUT SIX INCHES OFF THE GROUND AND HOLD THAT POSITION. AT THE SAME TIME COUNT RAPIDLY FROM 1001 TO 1030, WHILE WATCHING YOUR FOOT

• Demonstrate this to the suspect (though do not look at your foot when conducting the demonstration).

STEP 4

Say: DO YOU UNDERSTAND?

• Do not continue until the suspect indicates that they understand.

STEP 5

Say: BEGIN BY RAISING EITHER YOUR RIGHT OR YOUR LEFT FOOT.

• At the end of the count or after about 30 seconds, if the count is slow, tell the suspect to put their foot down if necessary.¹

2. The 4 Clues

In order to gauge whether you are intoxicated, law enforcement officials will typically watch for four “clues” of intoxication during the administration of the one-leg stand test:

1. You sway while balancing: This refers to side-to-side or back-and-forth motion while you maintain the one-leg stand position.
2. You use your arms for balance: You move your arms six or more inches from the side of your body in order to maintain balance.
3. You hop: You are able to keep one foot off the ground, but you resort to hopping in order to maintain balance.
4. You put your foot down: You are not able to maintain the one-leg stand position, putting your foot down one or more times during the 30-second count.

3. Reliability

According to government-sponsored studies, the one-leg stand test is only 65% accurate in determining whether a driver has an unlawful blood alcohol concentration.³ In short, more than one out of three people who fail the test are not intoxicated.

The one-leg stand becomes even more unreliable when any of the following is true:

• the floor surface is uneven, slippery, soft, or wet
• the lighting is inadequate
• you are elderly (over 60), overweight by 50 or more pounds, or have problems with your back, legs, feet, or inner ear
• you are mentally disabled or have brain damage
• You are wearing unsuitable footwear or clothing inhibiting your movements
• the officer does not time the test correctly
• the officer moves during the test, distracting you
• you are nervous and anxious, which is typical during a DUI investigation

4. Other Field Sobriety Tests

The one-leg stand test is one of three standardized field sobriety tests (SFSTs). The other two are:

• the horizontal gaze nystagmus test (the eye test) and
• the walk and turn test.

These three tests are considered “standardized” mainly because they have been the focus of various scientific studies noticeably establishing the connection between the three tests and DUI impairment.

Out of all the standardized field sobriety tests administered by law enforcement officials, the one-leg stand test has proven to be the least scientifically reliable.⁴

Frequently-Asked-Questions

Do I have to take the tests?

No. Field sobriety tests including the one-legged stand are not mandatory, so you can politely decline to take them. However, police will likely arrest you for DUI anyway based on other factors.

Will I lose my license for refusing the tests?

No, though the DMV will revoke your driver’s license for a year if you refuse the evidentiary breath or blood test following your arrest. This is true even if your DUI charges get dropped.

Can I still be arrested if I pass the tests?

Yes, police can still arrest you for DUI even if you score perfectly on all the field sobriety tests. Police will claim they have “probable cause” to arrest you due to other factors, such as:

• bloodshot or glassy eyes,
• slurred speech,
• failing the preliminary breath test, and/or
• the smell of alcohol or marijuana.

How can it be challenged in court?

If you fail the one-legged stand test or any of the other field sobriety tests, we can present the following arguments to challenge the results:

1. Field sobriety tests are unreliable;
2. The setting was not conducive for the test;
3. You had a physical or medical condition that caused the failing score; and/or
4. The police committed errors, such as giving you improper instructions.

Therefore, it is possible to win a DUI case even if you failed the field sobriety tests.

What if the police say I failed when I know I passed?

If you believe you passed the one-legged stand test or the other field sobriety tests, we may be able to:

• recover the police’s dashcam and bodycam footage showing you taking the tests and/or
• interview eyewitnesses who saw you take the tests.

Once we show prosecutors this evidence, they may agree to reduce or drop your DUI charges.