Our Commonwealth has taken important steps forward with regard to the law and marijuana.

The appalling number of people jailed for violations of marijuana laws made decriminalization requisite. The research that finds 25 percent reductions in opioid overdose in states with medical marijuana laws, and the compelling benefits for patients with pain and other conditions, appropriately encouraged Massachusetts to follow suit with such a law in 2012.

Inconclusive research about marijuana’s role as a so-called gateway to drug abuse and addiction allows a divergence of opinions about how to vote on Question 4.

However, the evidence of the negative impact of THC on attention, memory, mood, and educational performance; studies that suggest marijuana use among adolescents can “prime’’ young brains to develop an appetite for subsequent drug use; and the unknown safety issues associated with increased availability are not baseless fears. They should make us quite cautious about taking this next step.

I advocate voting “no’’ on Question 4.

Nicholas Covino

Newton

The writer is president of

William James College.