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Challenges to Field Sobriety Tests

Field sobriety tests are the roadside tests the police conduct during a traffic stop when they suspect the driver may be impaired. These tests can be helpful for the police to gather evidence to support an arrest but they are rarely helpful for drivers. In Missouri, you can refuse to submit to these tests, and in many cases, you should refuse. 

Just because the police arrested you for a DWI after reportedly “failing” the field sobriety tests does not mean that those tests were accurate. Your Missouri DWI defense lawyer can challenge the results of these tests in court to help your case. If you are facing DWI charges, contact the Joshua Wilson Law Firm for a case evaluation in Raymore, Missouri.

Standardized Field Sobriety Tests

There are three primary Standardized Field Sobriety Tests: that are used in impaired driving traffic stops. If the police officer suspects the driver may be driving while intoxicated (DWI), the officer will likely ask the driver to complete a series of tests and grade the driver on their completion of the tasks. These SFSTs include:  

  • Walk-and-Turn Test
  • One-Leg-Stand Test
  • Horizontal Gaze Nystagmus (HGN) Test

Walk-and-Turn Test

During the walk and turn test, the police officer has the driver walk in a straight line, one foot in front of the other, for a number of steps. The driver then has to turn around and return, heel-to-toe. 

There are specific “clues” the police look for during the test to indicate the driver did not pass the test. The clues in the walk-and-turn test include: 

  • Cannot keep balance
  • Start too soon
  • Stops before taking the full number of steps
  • Takes too many steps
  • Does not walk heel-to-toe
  • Steps off the line
  • Swings arms to balance
  • Improper turn

One-Leg-Stand Test

The one-leg stand (OLS) test consists of standing with your heels together and arms to the side. Upon instruction, the driver is to raise one leg about 6 inches off the ground, watching the raised foot. While standing on one leg, the driver is to count out loud, “one thousand and one, one thousand and two,” and so on, until told to stop. 

The clues that the police are looking for in the OLS test include: 

  • Using arms to balance
  • Swaying
  • Hopping
  • Putting foot down too early

Horizontal Gaze Nystagmus (HGN) Test

The HGN test is an eye test. The driver keeps their head still and is told to follow a pen, finger, or other stimulus with eyes only. The eyes will naturally demonstrate an involuntary shaking or movement at a certain deviation, which may occur more noticeably and earlier in impaired drivers. The police look for:

  • Lack of smooth movement
  • Distinct nystagmus and maximum deviation
  • Angle of onset (before 45 degrees)

How to Challenge Field Sobriety Tests  

The prosecutor in a DWI case will try to use the results of the SFSTs to show that the police officer had probable cause to arrest the driver for a DWI. However, your Missouri DWI lawyer can challenge the use or reliability of these tests in your court case. There are a number of problems with the reliability of these tests that your attorney can investigate and explain to the judge or jury. 

Police Training in SFSTs

Police officers generally go through a brief training program to learn about field sobriety testing, including how to give the tests, what to look for, and interpreting sobriety tests. However, there is always some level of subjectivity and not all police officers may give the same instructions, look at tests the same, or properly evaluate the test. An officer may have taken the test years ago and never taken a refresher course to brush up on their skills or knowledge. 

Giving the wrong instructions, skipping a step, or being unclear about the test can cause the test subject to fail. The police officer may claim they gave the proper instructions and blame the driver for failing the test.

Similarly, failing to properly observe the test subject is necessary for a fair evaluation. The police officer may be distracted, look away from the test, or leave the driver holding the position for too long, making them eventually fail the test. 

Other Explanations for Failed Tests

There are a number of other reasons why a driver could “fail” one or more of the field sobriety tests that are totally unrelated to alcohol or drugs. Reasons for failure to complete the test could include: 

  • Uneven ground on the side of the road
  • Shoes and clothing
  • Lack of lights or lights in the eyes
  • Speeding traffic nearby
  • Flashing police lights
  • Temperature or weather
  • Medical conditions
  • Age
  • Nervousness
  • Overweight
  • Medications
  • Physical injuries
  • Illness

What Happens if I Say No to Field Sobriety Tests? 

Many drivers feel pressured to submit to field sobriety tests. The police officer may make it seem like you don't have a choice or try and make it seem like things will go better for the driver if they do the test. However, it is your right to refuse a field sobriety test.

The police may say that if you refuse the test they will arrest you. However, they were probably going to arrest you anyway and are just using the tests to gather more evidence to use against you. Even if you pass the field sobriety tests, the police could still place you under arrest for a DWI. 

Refusing a chemical test after a DWI arrest in Missouri will result in a suspended license. However, there are no direct consequences for refusing a field sobriety test. Because these tests can be subjective and unreliable, you may not want to place much faith in these so-called tests. 

How an Experienced Missouri DWI Defense Lawyer Can Help

An experienced Missouri DWI defense lawyer understands how the police conduct SFSTs and knows what to look for in challenging these test results. Your DWI lawyer will be able to review the evidence in your case, review the police record and any other video, audio, or photo evidence to prepare your defense. 

Cass County criminal defense attorney Joshua Wilson has years of experience helping clients avoid DWI alcohol and DWI drug convictions. Contact the Joshua Wilson Law Firm today at (816) 331-9968 for a consultation.

Don't Hesitate To Contact Us Today

Time is of the essence in the majority of legal matters. If you are in need of legal representation for your family or criminal matters, contact The Joshua Wilson Law Firm at (816)331-9968 to begin your case evaluation today.

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