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Seeing Commonwealth v. Gerhardt in Action

I found myself in district court last week—it was a trial readiness day, and so the room was abuzz with attorneys trying to broker pleas and argue motions in anticipation of the trials that would be held within the next few days. Generally, the motions were heard without incident. The court allowed countless motions to “exclude the Horizontal Gaze Nystagmus test,” “sequester the witnesses,” and “keep out the defendant’s breath test refusal” without even an objection from the Commonwealth.

But finally, a few hours later, a motion was heard that did not receive an automatic answer. The defense lawyer in an OUI drug case argued that under the recent Commonwealth v. Gerhardt decision, the Commonwealth’s officer should be precluded from testifying to his assessment that the driver had been “under the influence of marijuana.” Counsel noted, succinctly, that in Gerhardt, the Massachusetts Supreme Judicial Court held that unlike in a case where it is alleged that the defendant was operating under the influence of alcohol, where an officer may offer lay opinion as to defendant’s state of sobriety, no such lay opinion can be offered where it is alleged that the defendant is under the influence of marijuana because there is no scientific consensus on the appearance of someone impaired by marijuana. Commonwealth v. Gerhardt, 477 Mass. 775, 785 (2017).

The court further held that “[w]here there is no scientific consensus on what, if any, physical characteristics indicate marijuana intoxication, no lay opinion can be admissible as common knowledge or understanding on that subject.” Id. at 786. According to this holding, in a case where the alleged substance is something other than alcohol, “[a] lay witness may testify concerning a defendant’s observable appearance, behavior, and demeanor, but may not offer an opinion as to the defendant’s sobriety or intoxication.” Id.

As is true in any case, the jury is the ultimate arbitrator of the facts—so are there any implications to precluding the officer from testifying to his opinion as to whether the operator was under the influence of marijuana? Can’t the jury make that determination for themselves with the aid of the officer’s other observations? The bigger issue is that while the holding of Gerhardt acknowledges that there are four common physical manifestations of marijuana use, “red and/or bloodshot eyes, a lack of convergence, eyelid tremors, and drowsiness,” these characteristics have not been scientifically shown to demonstrate to marijuana intoxication. Id. (emphasis added). Therefore, an officer could testify that he or she observed that the defendant to appeared tired and had red, bloodshot eyes, but the officer could not say that the defendant was under the influence marijuana because there is no scientific consensus that those characteristics necessarily indicate impairment.

But, if there is allegedly no consensus as to what someone impaired by marijuana looks like, then how can a jury possibly know beyond a reasonable doubt whether someone was under the influence of marijuana in a marijuana OUI case? Should a Drug Recognition Expert (“DRE”) be required to report to the scene of every instance of potential marijuana-impaired driving so that they will be able to offer expert testimony instead? Requiring the appearance of a DRE to every scene could be problematic however, because there are only approximately 141 certified DREs in Massachusetts, out of a police force of approximately 18,342—roughly 0.8%. It is therefore unlikely that a DRE could testify about a defendant’s impairment in each case, and so it falls back on the jurors to use their common sense and life experiences while they make their finding. But, how can they? The Gerhardt decision demonstrates that there is still a lot that we in the Commonwealth do not understand about marijuana and this trickiness related to officer’s testimony is only another example of something that might have required some additional thought before marijuana’s legalization in Massachusetts.


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