On January 6, 2017 the Massachusetts Supreme Judicial Court will hear oral arguments in the case of Commonwealth v. Thomas Gerhardt. This case raises the issue of whether field sobriety tests, which are routinely used to determine whether someone is under the influence of alcohol, can additionally be used to be determine if someone is driving under the influence of marijuana. Field sobriety tests have been studied extensively with relation to alcohol, and they are accepted as being proper evidence in the prosecution of driving under the influence of alcohol. However, the field sobriety tests have never been studied with regards to whether or not they can help determine if a person is impaired by marijuana. Attorney DelSignore filed an Amicus Brief on behalf of the National DUI College, an organization he has been a member of since 2007.
A judge in the district court ruled that these tests are inadmissible because they are unreliable and do not have any scientific support behind them. The judge concluded that whether someone passes or fails a nine step walk and turn or a one-leg stand does not help a jury determine whether the defendant is under the influence of marijuana. The Government argued that these tests do in fact have relevance because a persons reduced balance and the ability to follow instructions is a correlated with impairment by marijuana just as it is for alcohol.