Unlike a Breathalyzer or blood test, field sobriety tests do not fall under the implied consent law in Washington. While some drivers may feel that refusing to comply with an officer's request to complete a field sobriety test might indicate guilt even if there is none, this is not necessarily always the case. Additionally, there is a fair amount of skepticism over whether these types of tests are even accurate for determining intoxication for a DUI charge.
Even though the various field sobriety tests are somewhat standardized, an officer's interpretation of a driver's ability to complete them is not. These tests are highly subject to a police officer's personal opinion, and even two very minor mistakes may give some an adequate cause for arrest. The three different tests that comprise the field sobriety test are the walk and turn, the one-leg stand and the horizontal gaze.