Field sobriety tests are crucial tools used by law enforcement. They determine whether a driver is impaired by alcohol or drugs. They help officers decide whether further action, such as arrest or extra testing, is necessary. So, how many field sobriety tests are required?
Typically, law enforcement officers will administer three standard field sobriety tests. They are to assess whether a driver is impaired. These include the Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand tests. Still, the number can vary based on the situation and officer discretion.
Understand the types of tests and their applications. This can clarify their role in proving if a driver is impaired by drugs or alcohol. Read this extensive article to learn more.
Standard Field Sobriety Tests
The most commonly used field sobriety tests are standardized by the National Highway Traffic Safety Administration (NHTSA). They include three specific assessments. They are as follows:
Horizontal Gaze Nystagmus (HGN)
The Horizontal Gaze Nystagmus (HGN) test is used by police to check if someone can be drunk. An officer moves an object like a pen from one side to another in front of the eyes. He watches for nystagmus—when the eye jerks uncontrollably. When alcohol is in the system, this jerking happens more and sooner.
Studies show that this test accurately indicates impairment about 88% of the time.
Walk And Turn (WAT)
The walk-and-turn test helps police determine whether someone can be under the influence. A person is asked to walk nine steps heel-to-toe along a straight line. Then, turn on one foot and walk back the same way. This test examines balance, coordination, and how well someone follows directions.
Research shows this test correctly identifies impairment in about 79% of cases.
One Leg Stand (OLS)
The One Leg Stand test is another way police check for impairment. In this test, a person must lift one foot about six inches off the ground. Then, they must count out loud until asked to stop. It tests a person’s balance, coordination, and ability to pay attention.
Studies indicate that this test accurately identifies impairment about 83% of the time.
Non-Standardized And Additional Tests
Besides standardized tests, officers can use other tests to assess impairment further. These are non-standardized and additional tests. They include the following:
Finger-To-Nose (FTN)
The Finger-to-Nose test is used by police to assess whether someone can be impaired. The individual closes their eyes and leans their head back. Then s/he tries to touch their nose with their index finger’s tip. The test checks how well someone can control their body and perform precise movements.
It’s a helpful test but, like other field sobriety tests, lacks widely published statistics for accuracy.
Romberg Balance Test
The Romberg Balance test is a method police use to check for impairment. In this test, a person stands with their feet together, head back, and eyes closed. S/he tries to guess when 30 seconds have passed. It tests a person’s balance and their internal sense of timing.
While it provides valuable information on a person’s condition, specific accuracy statistics for this test are not as commonly reported as those for standardized field sobriety tests.
Alphabet Recitation
The Alphabet Recitation test is another tool police use to detect impairment. A person is asked to recite part or all of the alphabet. It tests their mental sharpness and ability to concentrate on a specific task. This test evaluates how well someone can focus and follow directions.
Although it is frequently used, detailed statistics on its accuracy are less common compared to other more standardized field sobriety tests.
Factors Influencing Test Selection
Several factors influence the choice and effectiveness of field sobriety tests. They include the officer’s discretion, the suspect’s cooperation and environmental conditions. Let’s learn more about them.
Officer’s Discretion
The training and experience of a police officer are essential in deciding which field sobriety tests to use. Officers choose tests based on what they see and how the suspect acts. Well-trained officers can better determine which tests will most accurately show if someone is impaired.
Still, specific statistics measuring the impact of an officer’s experience on test choice and accuracy are not commonly available.
Suspect’s Cooperation
A suspect’s willingness to participate in field sobriety tests impacts which tests the police decide to use and how they are performed. When a suspect cooperates, officers can use more complex tests. Those need careful listening and following instructions.
When a suspect is not cooperative, more straightforward tests can be chosen. Reliable statistics on how cooperation affects the outcome of these tests are not typically reported.
Environmental Conditions
Weather, lighting, and road conditions can affect how field sobriety tests are conducted. For example, walking in a straight line on a slippery road. Again, performing balance tests in solid winds is harder. Poor lighting can also make it difficult for officers to see clearly.
These factors can influence the accuracy of the tests. Specific statistics detailing the impact of these conditions on test outcomes are not usually provided.
Legal Requirements And Guidelines
Both standardized procedures and state-specific laws govern field sobriety tests. Let’s learn the legal requirements and guidelines in detail. They are as follows:
Standardized Testing Procedures
The National Highway Traffic Safety Administration (NHTSA) sets guidelines. Police must follow them when conducting field sobriety tests. The rules help ensure the tests are done right. They also make the results more accurate and legally sound.
Following these guidelines helps maintain consistency across different cases. Statistics show that when NHTSA guidelines are properly followed, the accuracy of tests like the HGN can be as high as 88%.
Variability In State Regulations
Each state in the U.S. can have its own rules on how field sobriety tests are given and judged. This means the same test can be done differently or judged by different standards. It depends on where you are. These state-specific rules ensure that tests are appropriate for local laws and conditions.
There are no widespread statistics on how these variations affect test results. This is because practices and regulations vary greatly from state to state.
Admissibility In Court Proceedings
Field sobriety test results must meet high standards for use in court. The tests must be done exactly as the rules say, or the results won’t be considered good evidence. This is important to ensure that the evidence is fair and reliable.
When these tests are properly conducted, they have been shown to accurately indicate impairment about 88% of the time. For example, Horizontal Gaze Nystagmus. This high accuracy helps make them trustworthy in court cases. For this reason, it is often not in one’s best interest to participate in field sobriety testing as the evidence will invariably be used against you.
Alternatives To Field Sobriety Testing
Other methods can be employed when field tests are inconclusive or not feasible. These include chemical breath tests and blood alcohol concentration (BAC) testing. They also include advanced drug screening methods. Let’s learn more about them.
Chemical Breath Tests
Breathalyzers are devices used by police. These are to check if someone has been downing alcohol. By analyzing a breath sample, these devices can measure how much alcohol is in someone’s breath. This gives a clear idea of how impaired a person can be.
Studies have shown that breathalyzers, if they are properly calibrated, are accurate, often within a margin of error of about 0.005% blood alcohol concentration. This makes them a reliable tool for assessing whether someone is too impaired to drive.
Blood Alcohol Concentration (BAC) Testing
Blood tests are a very accurate way to measure how much alcohol someone has in their blood, giving a clear picture of impairment. Besides alcohol, tests on blood, urine, or saliva can detect different drugs in a person’s system.
These tests are reliable because they measure the actual chemicals in the body. For instance, blood tests for alcohol can be accurate up to 99% of the time, making them a trusted method in medical and legal settings.
Advanced Drug Screening Methods
Advanced drug screening methods include testing saliva, urine, or blood to find out if someone has used drugs. These tests can detect a wide range of drugs, from marijuana to prescription medicines.
They are highly accurate, with urine tests, for example, being correct about 95% of the time. These methods help police and doctors know for sure if drugs are in a person’s system, ensuring they get the right help or legal response.
FAQs
1. What Is The Most Common Field Sobriety Test?
The most common field sobriety test police use is the Horizontal Gaze Nystagmus (HGN) test. In this test, an officer watches the suspect’s eyes as they follow a moving object, like a pen, to see if there is any unusual jerking of the eyes, which can indicate impairment due to alcohol.
2. Why Are Multiple Field Sobriety Tests Administered?
Multiple field sobriety tests are administered to assess impairment accurately. By using various tests, such as the Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand, officers can evaluate a suspect’s balance, coordination, and eye movements to decide if they are under the influence.
3. How Many Field Sobriety Tests Are Typically Administered During A Traffic Stop?
Typically, three field sobriety tests are administered during a traffic stop to assess impairment. These include the Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand tests. Together, they help officers evaluate a driver’s balance, coordination, and ability to follow instructions.
Conclusion
Field sobriety tests are important tools that police use to stop impaired driving. When a police officer thinks a driver can be under the influence of alcohol or drugs, they use these tests as a first step. This is to figure out how impaired the driver is.
The most common tests are the Horizontal Gaze Nystagmus, where the officer checks the driver’s eye movements. Then, the Walk and Turn, where the driver must walk in a straight line and turn. Also, the One Leg Stand, where the driver must balance on one foot.
These tests help the officer decide if the driver needs more testing to measure alcohol or drug levels more accurately. Knowing how these tests work and why they’re used helps us understand their role in proving a case in open court. Depending on one’s performance of field sobriety testing, it may not be in one’s best interest to agree to test. For more information, or to schedule a free consultation, do not hesitate to contact the attorneys at Leverson Budke, P.A. today.
