Many motorists are pulled over in California each day on suspicion of driving under the influence of alcohol or drugs. Depending on the situation, police officers may want to have the driver submit to field sobriety tests used to determine whether they are impaired. It is important to note that police cannot pull motorists over on a whim and must have reasonable cause to believe the driver is operating under the influence. Inaccuracies of field sobriety tests can result in an innocent person being arrested or charged with driving under the influence (DUI). Those with questions may want to consider contacting SLM Law at (310) 443-4119.

Field Sobriety Tests in California

When someone is pulled over on suspicion of drunk driving, that person may be asked to perform physical and cognitive tests which include:

  • Horizontal gaze nystagmus, which involves the officer measuring the involuntary movements of the driver’s eyes that could indicate intoxication
  • One-leg stand in which the officer will request the driver stand on one leg and maintain balance while counting
  • Walk-and-turn which requires the driver to walk a straight line without using the arms to balance or falling over, then turning back and walking the same straight line while maintaining balance

Police officers use field sobriety tests to determine a driver’s ability to follow directions and to measure their coordination skills and balance. The problem with these tests is that some are very difficult for sober motorists to pass.

When Is it Legal for an Officer to Pull a Motorist Over?

In California, an officer must have probable cause that a driver has violated the law in order to pull them over. A police officer cannot conduct a vehicle stop for no reason, and to pull over someone an officer suspects of driving under the influence does not require the violation be related to impaired driving.

For example, if an officer suspects a motorist may be impaired but has not noticed the driver weaving or drifting out of their lane, the officer can still pull the driver over if the brake lights do not work, a turn is made without signaling, or the driver does not come to a full stop at a stop sign. Any violation of the law is probable cause to conduct a traffic stop. Those with questions regarding the validity of a traffic stop may want to consider reaching out to SLM Law.

Issues with California Field Sobriety Tests

Field sobriety tests are not scientific and often rely on how an officer perceives the driver and the circumstances. According to the United States Department of Justice, a 1991 publication titled “Alcohol, Drugs, and Driving” found that field sobriety tests did not always identify impaired motorists accurately except when those individuals had a high blood alcohol concentration (BAC). Additionally, there are issues that may contribute to inaccuracies of field sobriety tests.

Horizontal Gaze Nystagmus Test

Involuntary eye movement or drift occurs naturally when a person gazes to the side and is normal. The issue with this test is that certain legal medications such as those used to control seizures, certain inhalants, and barbiturates or depressants prescribed to someone can make it impossible to pass this test. Certain eye diseases or conditions may also affect test results.

Walk-and-Turn Test

In this test the driver is asked to walk heel-to-toe for nine steps in a straight line. There are health issues and physical limitations that can cause someone to fail this test. Age, location, and time of day can also impact a person’s ability to properly perform this test.

One-leg Stand Test

It is difficult for many people to stand with one leg six inches above the ground for 30 seconds on a normal day. When someone is in a situation that makes them nervous, 30 seconds can seem like an eternity. Other reasons someone may fail this test include health or physical limitations, rain or other environmental conditions, and being distracted by something unexpected such as bright headlights.

Non-Standard Field Sobriety Tests

A police officer may administer field sobriety tests that are non-standard and not recognized by the National Highway Traffic Safety Administration (NHTSA). These include:

  • Having the suspect touch a finger to the tip of the nose while eyes are closed
  • Having the suspect count the number of fingers the officer has raised while standing with feet together with the head is tipped backward
  • Having the suspect recite the alphabet

When a police officer attempts to use these non-standard field sobriety tests in court, a California DUI defense attorney can move to have the results suppressed.

Consider Scheduling a Consultation with SLM Law

Unfortunately, the inaccuracies of field sobriety tests can be a factor in DUI charges. Those with questions or who need skilled legal guidance should feel free to reach out to SLM Law at (310) 443-4119.