In a statement, the Yes on 4 Campaign expressed condolences to Reisa Clardy on the loss of her husband and said Njuguna, if convicted, should be "punished to the fullest extent of the law."
Massachusetts voters approved a medical marijuana program in 2012 and previously decriminalized possession of small amounts of the drug. The medical marijuana law does not contain any specific language addressing impaired driving, but state law makes it illegal to drive under the influence of drugs, including marijuana.
Recreational use of marijuana is currently legal in Alaska, Colorado, Oregon, Washington state and the District of Columbia. Along with Massachusetts, voters in Arizona, California, Maine and Nevada will decide legalization measures next month.
Opponents of the Massachusetts question pressed their case that legalization would lead to more impaired crashes, citing research that marijuana use can affect peripheral vision and coordination and can slow drivers' decision-making and reaction time.
A recent study by the AAA Foundation for Traffic Safety found that after Washington state legalized recreational marijuana 2012, fatal crashes involving drivers that had recently used marijuana doubled, opponents said at a Statehouse news conference.
Jim Borghesani, a spokesman for Yes on 4, dismissed the study as flawed, noting its authors acknowledged that the data did not reveal whether drivers with THC, the psychoactive chemical in marijuana, in their system were actually impaired at the time of a crash.
"Right now, police officers have every ability to pull over someone who is driving impaired and take them off the road," Borghesani said.
Essex District Attorney Jonathan Blodgett, an opponent of legalization, said police and prosecutors lack an effective way of determining what constitutes marijuana impairment, though such tests are being developed.
"We are years away ... from an effective, standardized, court-approved roadside test to measure a driver's THC level, and even if such a test existed, there is no scientific consensus as to what level of THC in the blood constitutes impairment," Blodgett said.