The Standard Field Sobriety Test (SFST) is used by police in Michigan to help determine whether a driver is drunk. The tests were created to measure a driver’s balance and coordination, as well as their ability to focus while an officer gives instructions.

While some studies claim SFSTs have proven to be 90% accurate, statistics from the National Highway Traffic Safety Administration (NHTSA) show the tests are correct only 65% to 77% of the time.

Three parts of a field sobriety test

NHTSA began developing a standardized system to detect drunk drivers in the 1970s. While officers started using field sobriety tests in the early 1980s, the current three-part battery has been used for nearly 20 years. The tests include:

  • Horizontal gaze nystagmus: An officer shines a light in your eyes looking for involuntary movements of the eyeballs or an inability to follow the light.
  • One-leg stand: You will be asked to stand on one foot and count upward from 1,001 until told to stop. The officer is looking for a swaying motion, using your arms or hopping to maintain balance or putting your foot down early.
  • Walk-and-turn: The officer asks you to take several steps heel-to-toe in both directions to measure balance and your ability to understand and follow instructions.

There are many reasons why people fail SFSTs

Drivers who fail one or more of the tests often have legitimate reasons, such as age, medical conditions, injuries or due to the medications they are taking. Once officers suspect a driver has been drinking, they will ask them to take a preliminary breath test. You can refuse, but you may be charged with a separate infraction and be required to take a chemical test.

Seek legal help if charged with OWI

Michigan drivers with OWI convictions face significant jail time, fines and fees, suspended driving privileges and many other consequences, such as increased insurance rates, which can double or triple. An experienced defense attorney will protect your rights, making sure an officer had probable cause to stop you and correctly performed sobriety tests. A successful defense can result in less jail time, reduced fines and, in some cases, charges being dropped.