The state’s highest court today ruled police officers can testify to observations made during field sobriety tests of drivers suspected of being under the influence of marijuana, but the results of the tests may not be used as sole evidence to convict someone of driving under the influence.
“There is as yet no scientific agreement on whether, and, if so, to what extent, these types of tests are indicative of marijuana intoxication.” the court found.
The case, Commonwealth v. Gerhardt, stems from a 2013 traffic stop during which the defendant, Thomas Gerhardt, failed multiple field sobriety tests after being pulled over by a state trooper in Millbury.
Gerhardt’s attorney argued to the SJC that failing field sobriety tests does not necessarily mean a driver who has used marijuana is legally impaired.
The court agreed.
“The research on the efficacy of FSTs to measure marijuana impairment has produced highly disparate results,” the decision states. “Some studies have shown no correlation between inadequate performance on FSTs and the consumption of marijuana; other studies have shown some correlation with certain FSTs, but not with others; and yet other studies have shown a correlation with all of the most frequently used FSTs.”
The decision includes an instruction to juries stating the results of a field sobriety test may never be used solely to convict someone of driving under the influence of marijuana, but police officers may testify to what they see when putting a motorist through the tests.
“We conclude that, to the extent that they are relevant to establish a driver’s balance, coordination, mental acuity, and other skills required to safely operate a motor vehicle, FSTs are admissible at trial as observations of the police officer conducting the assessment,” the decision states.
It will be up to a particular jury as to how much weight, if any, to give that testimony in determining a driver’s guilt or innocence, the decision states, but the field sobriety tests themselves cannot be used as “scientific tests establishing impairment” due to marijuana use.
“Because the effects of marijuana may vary greatly from one individual to another, and those effects are as yet not commonly known,” the decision states, “neither a police officer nor a lay witness who has not been qualified as an expert may offer an opinion as to whether a driver was under the influence of marijuana.”
credit:bostonherald.com
