Police officers who suspect people of drunk driving must look for supporting evidence. They must have probable cause to believe a crime occurred if they intend to take a motorist into state custody.
Police officers who have pulled drivers over usually ask questions about the motorist’s prior activities. They attempt to gather documentation of impaired ability and proof that the driver knew they should not operate a vehicle.
Officers may ask drivers to exit their vehicles and perform field sobriety tests. Many motorists believe that these physical tests can prove that they are not currently under the influence. Contrary to what they expect, field sobriety tests can often provide the probable cause for an arrest.
False positives are somewhat common
The three standardized field sobriety tests have a basis in medical science. The tests look at physical functions often impacted by alcohol consumption, such as balance, memory and muscle spasms. However, people can fail those tests due to anxiety and a variety of different medical conditions.
Drivers who expect to quickly establish that they are sober enough to legally drive may actually put themselves at risk of arrest. Those who experience anxiety when interacting with authority figures and those with pre-existing medical conditions may need to consider politely but firmly refusing requests for field sobriety tests.
The law does not force drivers to submit to these tests and refusing them could prevent innocent motorists from unintentionally implicating themselves. Drivers who know their rights are less likely to make mistakes that put them at a disadvantage later.
Those who have already failed a field sobriety test may need help responding to their pending drunk driving charges. Providing an alternate explanation for poor test performance can potentially be part of a comprehensive criminal defense strategy.