If a police officer suspects that you’re drunk driving, he will typically ask you to perform a series of field sobriety tests (FST).
These tests usually include
- the horizontal gaze nystagmus test,
- the nine step walk and turn,
- the one-leg stand,
- the alphabet recital, and
- the reverse counting test (when you’re asked to count backwards from one arbitrary number to another).
The officer can conclude that you’re impaired based on your FST performance. Also, at trial he may testify about what he observed during the FST without being a qualified expert.
According to Massachusetts case law, the FST can
measure a person’s sense of balance, coordination, and acuity of mind in understanding and following simple instructions, {and} a lay juror understands that intoxication leads to diminished balance, coordination, and mental acuity from common experience and knowledge.
Commonwealth v. Sands, 424, Mass. 184, 188 (1997)
Therefore,
[w]hat [the officer] observed, both before and during the sobriety tests, [is[ within the scope of a juror’s common experience of intoxication.
Commonwealth v. Moreno, 102 Mass. App. Ct. 321, 325 (2023).
Consequently, the officer does not need to qualify as an expert before offering such testimony.