In November 2016, Massachusetts voters legalized recreational marijuana use by passing “The Regulation and Taxation Marijuana Act” (also known as ballot “Question Four”). With the passage of the new legislation, many are concerned about marijuana users driving on Massachusetts roadways. But how, if at all, does marijuana decriminalization affect Massachusetts OUI (operating under the influence) law?
The short answer—it has no effect. Here’s why.
In Massachusetts, it’s illegal to operate a motor vehicle while under the influence of marijuana, or any other drug. Under Massachusetts law, a person is “under the influence” if the substance ingested by the person “diminished the [person’s] ability to operate a motor vehicle safely.” (Mass. Gen. Laws Ann. ch. 90B, § 8(a)(1) (2016); Com. v. Connolly, 394 Mass. 169 (1985).)
So, anyone who drives while impaired by marijuana (as defined above) can be convicted of an OUI. It doesn’t matter that the driver may have ingested marijuana legally. To dispel any doubt, the new law explicitly says that the decriminalization of marijuana doesn’t affect Massachusetts OUI or BUI (boating under the influence) law. (The Regulation and Taxation Marijuana Act, § 2(a) (2016).)