Question:

What should I do if I'm asked to take field sobriety tests?

Answer:

There are a wide range of field sobriety tests (FSTs), including heel-to-toe, finger-to-nose, one-leg stand, horizontal gaze nystagmus, alphabet recitation, modified position of attention (Rhomberg), fingers-to-thumb, hand pat, etc. Most officers will use a set battery of three to five such tests.

Unlike the chemical test, where refusal to submit may have serious consequences, you are not legally required to take any FSTs. The reality is that officers have usually made up their minds to arrest when they give the FSTs; the tests are simply additional evidence which the suspect inevitably "fails". Thus, in most cases a polite refusal may be appropriate.
Recently, many states have begun following the federally-approved (National Highway Traffic Safety Administration) "standardized" field sobriety tests. These consist of a battery of three tests:

• Heel-to-Toe (also referred to as "walk-and-turn")
• One-Leg Stand
• Horizontal Gaze Nystagmus

All other field sobriety tests are disapproved. And unlike non-standardized tests, in which the officer subjectively decides whether the suspect passes or fails, the SFSTs are scored objectively — that is, a numerical score is assigned according to specific errors, or "clues".