Field Sobriety Testing: Purpose, Process & Accuracy
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What is Field Sobriety Testing?
Field sobriety testing refers to a battery of physical and mental tasks administered by police to assess whether a driver is intoxicated or under the influence of any drug. The tests allow the officer to identify signs of impairment. It may be observed through an individual exhibiting poor balance, poor coordination, and an inability to effectively manage multiple tasks. Commonly, field sobriety tests are executed roadside in traffic stops when an officer suspects a person of being impaired.
The tests are uniform across the country to carry legitimacy in impairment. For instance, the National Highway Traffic Safety Administration (NHTSA) recognizes three standardized field sobriety tests (SFSTs) as valid means to determine if a person is intoxicated. The driver may then be taken for further testing, a breathalyzer or blood test, if they fail these tests.
Table of contents
- What is Field Sobriety Testing?
- How Do Field Sobriety Tests Work?
- Signs of Intoxication
- The Three Field Sobriety Tests (Standardized Field Sobriety Tests)
- Accuracy and Limitations of Field Sobriety Tests
- Can You Fail a Field Sobriety Test While Sober?
- Tests for Marijuana and Other Substances
- Can You Refuse a Field Sobriety Test?
- How To Pass A Field Sobriety Test?
- How to Avoid Field Sobriety Testing Situations
- Tips for Staying Sober
- Take Control of Your Sobriety with Our Support
How Do Field Sobriety Tests Work?
These field sobriety tests are a series of tests looking for incipient signs of impairment in balance, coordination, and aspects of cognitive performance. These three most standardized tests include:
- Horizontal Gaze Nystagmus Test (HGN)
- Walk-and-Turn Test
- Single-Leg Standing Test
Each test is designed to test aspects of physical and mental functioning and has been shown to help officers make better decisions about a driver being impaired.
Signs of Intoxication
Officers will look for some of the critical signs of intoxication, such as the following, among others, when administering various field sober tests:
- Slurred speech
- Red, bloodshot eyes
- Alcohol or drug smell
- Nausea or vomiting
- Confusion or trouble concentrating
- Lag or lethargy
- Over-talkativeness or increased euphoria
- Difficulty following directions
- Impaired motor functions, including inability to walk or loss of balance
- Delayed response, or slow reaction, to questions
These physical and behavioral signs can lead an officer to suspect that a person is impaired, prompting further testing.
The Three Field Sobriety Tests (Standardized Field Sobriety Tests)
The NHTSA recommends the following three significant tests:
-
Horizontal Gaze Nystagmus (HGN)
The HGN test looks into the involuntary jerking of the eyes, which is exaggerated just in case a person is intoxicated. During this test, the officer will have the driver follow a moving object – such as a pen or light – with their eyes. The officer looks for the following:
- Jerking of the eyes at extreme deviation
- Eye movements initiated prior to object movement
- The inability to follow the object smoothly
This test is highly reliable for detecting impairment due to alcohol.
-
Walk-and-Turn Test
This test tells whether the individual has balance and can follow instructions. The officer would request the driver to take nine heel-to-toe steps along a straight line, turn, and return back the same way. The following are some of the signs of impairment that include:
- Loss of balance
- Start the test before the instructions have been delivered.
- Not walking heel-to-toe
- Stepping off of the line
- Using arms to balance or stumbling
This test indicates motor and attention deficits.
-
One-Leg Stand Test
In the one-leg stand test, the driver is required to do some balancing on one foot while counting aloud for 30 seconds. The officer will look for clues such as:
- Swaying while keeping the balance
- Hopping to keep one’s balance
- Putting the foot down before it is time
- Using the arms to steady
These would indeed imply impaired physical coordination, denoting intoxication.
Accuracy and Limitations of Field Sobriety Tests
Field sobriety tests (FSTs) are also commonly administered by police officers to ascertain a driver’s intoxication status. The National Highway Traffic Safety Administration (NHTSA) revealed that FSTs correctly identify alcohol-impaired drivers with a BAC of 0.08% about 91% of the time; when considering possible explanations for false positives, this could be as high as 94%.
Despite their usefulness, FSTs result in a lot of false positives for various reasons such as medical conditions, injuries, age, prescribed medications, and some over-the-counter medications.
Conditions of the inner ear, for instance, or neurological conditions such as multiple sclerosis may impact balance and, consequently, such test results. The officer must investigate all such concerns before performing the test since these related factors can affect the test results.
Can You Fail a Field Sobriety Test While Sober?
Yes, you can fail a field sobriety test while sober. Many things could interfere with your ability to complete these tests, and it doesn’t relate to having alcohol or drugs in your system.
Medical conditions such as arthritis, inner ear problems, and neurological disorders, as well as age or trauma, can impair your balance and coordination. Some prescription medications also may affect your ability to take the tests successfully.
This would be a good time to make sure if you believe you have a legitimate reason why you may not pass the test, you tell the officer. This could be helpful if your case goes to court since it provides context regarding why such a test may or may not be indicative.
Tests for Marijuana and Other Substances
Field sobriety tests are primarily designed to detect alcohol impairment but are employed to observe the signs of impairment from other substances, such as marijuana. These tests, however, are less reliable when applied for drugs.
Drug recognition experts (DREs) can also be called in to assess symptoms of drug impairment. The police also inspect the pupils for conditions such as size and other movements that are not normal, which may indicate drug use during drug tests other than alcohol. Tests conducted on saliva, blood, and urine are commonly needed on many occasions to ascertain precisely drugs other than alcohol.
Laws regarding drugged driving, particularly with the use of marijuana, differ by state. Some states have defined specific thresholds for levels of THC alone in the blood, similar to limits on BACs for alcohol.
Can You Refuse a Field Sobriety Test?
In most states, you have the right to decline to take a field sobriety test. However, you may be subject to certain consequences as a result of your refusal. You may be subject to an immediate sanction for refusal, like losing your license, and even without FST results, police can arrest you for probable cause that you are impaired. For example, police may rely on behavior or your manner of speaking when arresting someone for suspected impairment without using the FST results.
While refusing this test might cut out some evidence against you, it does not guarantee that one could avoid legal consequences. In such situations, knowing your rights and the possible consequences of refusal are important.
How To Pass A Field Sobriety Test?
Passing a field sobriety test requires clear focus and paying close attention to the officer’s instructions. If you are asked to walk in a straight line or stand on one leg, among other actions, calmness and concentration are called for. Follow the officer’s directions, and don’t rush through the tests.
Still, balance and coordination are important; hence, keeping control of your movements will help. Also, avoid sudden gestures or actions, as these may be misconstrued to show intoxication. Remember, the tests are devised to demonstrate impairment, and a little ignorance in any respect may prove costly against you.
How to Avoid Field Sobriety Testing Situations
The most responsible thing one could do not to get into field sobriety testing and any further legal consequences is to make responsible decisions concerning substance use in the first place. Here are a few ways:
- Plan Ahead: If you know that you will be in a situation where there is a good chance alcohol or drugs will be used, make plans in advance for getting home safely.
- Designated Drivers: Always plan for a designated driver if you plan on drinking.
- Ride-Sharing Options: Be prepared at all times with ride-sharing services to avoid driving under intoxication, such as Uber or Lyft.
- Seek Treatment: At this stage, substance use as a problem may progress to a level where professional help is an important means of regaining control of one’s life.
Because you may make these proactive decisions, you will not have a problem with law enforcement, and the following consequences regarding a DUI charge can be avoided.
Tips for Staying Sober
- Surround yourself with support: Spend time with friends or peers who inspire and help encourage your goals in staying sober.
- Stay away from high-risk situations: Those in which the opportunity or pressure to drink and/or use drugs may be difficult to resist.
- Recovery support: Make sure to keep attending regular meetings or therapy to hold yourself accountable and focus on the goals of your sobriety.
Take Control of Your Sobriety with Our Support
At Bridges Sober Apartments, we are driven by a passion for helping people live sober lives, and this we achieve through our structured sober living homes. If it is to start or continue your sober life, then we provide you with a secure and structured environment where you can work toward your goals. Our team is here to help you build a life free from addiction.
Our services include, but are not limited to, counseling, sober activities, and a structured living environment that encourages long-term sobriety.
If you or someone you know is fighting sobriety, then Bridges Sober Apartments LA is just a phone call away today. Our team will be ready with this opportunity to take your next step into recovery and support you every step of the way in building a life full of purpose and fulfillment.
Table of contents
- What is Field Sobriety Testing?
- How Do Field Sobriety Tests Work?
- Signs of Intoxication
- The Three Field Sobriety Tests (Standardized Field Sobriety Tests)
- Accuracy and Limitations of Field Sobriety Tests
- Can You Fail a Field Sobriety Test While Sober?
- Tests for Marijuana and Other Substances
- Can You Refuse a Field Sobriety Test?
- How To Pass A Field Sobriety Test?
- How to Avoid Field Sobriety Testing Situations
- Tips for Staying Sober
- Take Control of Your Sobriety with Our Support