Understanding field sobriety tests

| Oct 31, 2019 | OUI Defense

A recent news report about a Massachusetts arrest helps illustrate an important point about OUI law enforcement and prosecution.

According to the report, police in historic Rehoboth said they received reports from the public about a dark sports car driving dangerously, and responded to the scene. Officers said they saw a dark Hyundai weaving and looking like it was about to drive off the road. An officer said he pursued the car for a short distance, watching it slow down, speed up cross the roadway’s center line several times.

When the vehicle stopped, police arrested the driver on suspicion of driving under the influence. Officers said they were unable to make the man appeared so incapacitated that they decided not to administer a field sobriety test. He was arrested and later released, but has been charged with OUI-related crimes.

While this case is routine in many respects, the lack of a field sobriety test is an important and somewhat unusual detail.

Police typically make drivers go through a field sobriety test soon after pulling them over on suspicion of driving under the influence of alcohol or drugs. In these tests, police observe the driver’s balance, physical abilities, attention span and other qualities that can indicate intoxication. They usually administer these tests before having the person do a chemical breath or blood test to determine their blood alcohol concentration, or BAC.

If police do not require a driver to take a sobriety or BAC test, it is probably because they think they have enough evidence to sustain an OUI charge without the test results. However, this evidence relies on their observations of the person’s driving and personal behavior.

One of the most important parts of OUI defense is understanding the evidence the prosecution has, and building a strategy tailored for attacking exactly that defense.