What are Field Sobriety Tests?
Field sobriety tests (FSTs) are a series of physical and mental exercises that are usually administered by police officers in DUI investigations. These tests are meant to test your balance, coordination and divided attention. Even though there are dozens of FSTs that are usually used by law enforcement agencies, only three of these tests are validated as reliable by the National Highway Traffic Safety Administration (NHTSA). They include:
- Horizontal Gaze Nystagmus (HGN) Test
Nystagmus is basically an involuntary jerking of the eyes that occurs when you move your eye toward the side. While there are different kinds of nystagmus that are influenced by alcohol, the one that is used in DUI investigations is the horizontal gaze nystagmus.
When administrating the HGN field sobriety test, the police officer will instruct you to follow (with your eyes) a stimulus to the right and to the left. The officer will note the angle at which your pupil begins to show nystagmus. An early beginning of nystagmus – at or before a forty-five-degree angle) - is linked to a high blood alcohol concentration.
Based on tests conducted by the San Diego Police Department, NHTSA believes that the horizontal gaze nystagmus test is 88 percent reliable. This means that 88 percent of the time this test will accurately establish whether a driver has a Blood Alcohol Concentration (BAC) of at least 0.08 percent.
- Walk and Turn (WAT) Test
This is essentially a “divided attention” field sobriety test that requires you to concentrate on both physical and mental tasks simultaneously. This test is often referred to as the 9-step test, the 9-step walk turn, the DUI straight line test, or the DUI walk the line test.
When subjected to the walk and turn test, you will be asked to follow and memorize instructions while performing certain physical movements such as pivoting around, taking 9 heel-to-toe steps on a real or imaginary line, and taking 9 heel-to-toe steps back. When performing this test, the police officer will watch out for various signs that may indicate impairment. Particularly, the officer will be looking to see if you will:
- Start too soon,
- Keep your balance,
- Stop while walking,
- Fail to touch heel-to-toe,
- Step off the real or imaginary line,
- Use your arms to balance,
- Fail to turn correctly,
- Take an incorrect amount of step.
NHTSA believes that there is a 79 percent correlation between poor performance on the walk and turn test and a Blood Alcohol Content of at least 0.08 percent.
- One Leg Stand (OLS) Test
This is the 2nd “divided attention” test of the 3 standardized FSTs. During the OLS test, the police officer will ask you to:
- Raise your foot about 6 inches off the ground,
- Maintain that position,
- Count from 1001 to 1030,
- Look down at your foot.
During this test, the police officer will be looking out for certain signs of impairment, such as swaying, hopping, using your arms to balance, or putting your foot down. NHTSA believes that there is an 83 percent chance that any driver who exhibits at least two of those signs during the OLS test has a BSA of 0.08 percent or more.
Nevertheless, NHTSA emphasizes that the high correlation between the three standardized FSTs and DUI impairment only applies when the tests are carried out under appropriate and safe conditions. The conditions that can affect the legitimacy of FSTs include:
- Surface conditions: The tests should be conducted on a surface that is hard, dry, level and non-slippery. This is to reduce the risk of falling. Furthermore, there should be sufficient room for the driver to perform the test.
- Lighting conditions: There should be adequate lighting to ensure that the driver can see the police officer and the ground clearly. If there’s inadequate lighting, the officer should use a flashlight.
- Auditory conditions: The environment should be fairly quiet so that the driver can hear the officer’s instructions.
For the standardized FSTs to be deemed valid, they must be carried out in the prescribed, standardized manner. In case any of the above elements is altered, the legitimacy of a field sobriety test may be compromised.
Besides the above NHTSA standardized FSTs, there are various other FSTs that are often used by California police officers in DUI investigations. They include:
- The hand pat test
- The finger-to-nose test
- The finger count test
- The Rhomberg balance test
The reason why NHTSA hasn’t standardized the above field sobriety tests is because of their correlation with DUI impairment has not been demonstrated just yet. Moreover, procedural administration of these tests varies greatly from one law enforcement officer to another. Therefore, the accuracy and/or legitimacy of these non-standardized FSTs is questionable.
Are Field Sobriety Tests Mandatory in California?
Good news is that field sobriety tests, standardized or not, are not mandatory. However, police officers don’t usually tell drivers this. Instead, they use the results of tests to justify the arrest and gather DUI evidence against drivers at the DMV or in court. You should know that it’s your right to politely refuse any FST. Refusing to take the test cannot be used against you.
While you have the right to refuse an FST, you do not have the right to refuse a chemical test (urine, blood, or breath test). Your refusal to a chemical test will be deemed as an admission of guilt on your part, and it can cause you problems with both the court and DMV systems.
If you get arrested after failing an FST, you will be tempted to argue, fight, curse, or spit at the officer. DON’T! Doing so will only make the situation worse, and additional charges may be made against you. It’s best to be calm, polite, and courteous. If interrogated, you can choose to exercise your Fifth Amendment right and remain silent. At this point, you can request to call a lawyer.
How Law Offices of Ross H. Sobel Can Help
Our skilled and experienced DUI defense attorney can defend you against DUI charges and secure the best possible outcome for your case. To get you off the hook, the attorney can use a wide range of defenses to challenge the FST results. The attorney could argue that:
- The tests were not conducted under appropriate conditions,
- A physical condition other than alcohol/drug intoxication caused you to perform poorly on the test, such as age, weight, sickness, pain, ear/leg/foot/back problems, etc.
- A mental condition other than alcohol/drug intoxication caused you to perform poorly on the test, such as a mental disability, mild brain damage, nervousness, etc.
- The officer exhibited forms of distractive behavior (such as walking around) that made you perform poorly on the test.
- You were wearing unsuitable attire, i.e. high heels, tight shoes, tight pants, beltless pants or jeans, gloves, or any other type of clothing that hampered your ability to perform the test effectively.
The consequences of having a DUI charge are serious and far-reaching. You may not only lose your driving license, but you could also spend some time in prison, pay hefty fines, or miss out on employment opportunities. Don’t let a field sobriety test stand in your way.
The Law Offices of Ross H. Sobel can offer you the best legal representation to ensure that the DUI charge resulting from a field sobriety test is dropped. Contact us or call us at 310-788-8995 today for a free consultation and to find out how we can help.