His concerns, voiced just after his committee submitted its report on the topic, arise from his role as both a father and a public official, he said.

For a year, state Senator Jason M. Lewis maintained strict neutrality as he studied marijuana legalization — interviewing 50-plus experts, scouring the research, and observing firsthand a state where it is legal. But now he is speaking out against the expected November referendum in Massachusetts.

“I am opposed to the likely ballot question because this is the wrong time for Massachusetts to go down this road, and a commercial, profit-driven market is the wrong approach to take,” the Winchester Democrat said.


Lewis, a onetime McKinsey & Co. consultant, laid out a wide-ranging case against the measure, arguments that could serve as a template for the opposition. And, as the debate heats up, it could vault the professorial legislator to a much more public role.

The proposed law would make possessing, using, and giving away 1 ounce or less of recreational marijuana legal for adults 21 and older as of Dec. 15, and it would allow retail sales to commence in January 2018.

State Senator Jason M. Lewis. Jonathan Wigg/Globe staff

Advocates say it would quickly begin to phase out the black market: ending more than a century of failed prohibition that has ensnared otherwise law-abiding citizens in the criminal justice system; diverting money from criminal syndicates to companies operating on the up and up; filling the state’s coffers with new tax dollars; and improving the health and safety of children by moving marijuana sales from the street to licensed stores that check IDs.

“We’re proposing a comprehensive, tightly regulated solution to the vast criminal enterprise that has flourished under a system that bans a substance less toxic, less addictive and less dangerous than alcohol,” said Jim Borghesani, a spokesman for the Campaign to Regulate Marijuana like Alcohol in Massachusetts, which is backing the ballot effort.


“Our opponents are offering stale, alarmist arguments that essentially preserve that failed system,” he added.

But Lewis, 47, said legalization may boost the accessibility of marijuana for youth and increase the perception among kids that pot is safe to use.

And he indicated that some worries about the Massachusetts criminal justice system are unfounded. He said criminal penalties for marijuana possession of an ounce or less have already been replaced with a system of civil penalties. And for most adults who use pot casually, there aren’t any criminal sanctions.

“Virtually nobody is actually being arrested and going to jail for marijuana use,” he said, adding that as best as his staff can tell, fewer than 10 people a year are incarcerated for possession of more than an ounce of pot, and most of those people are getting locked up for another offense.

The special Senate committee’s report did not explicitly endorse or reject the legalization proposal. But it did raise numerous concerns about how it would play out in Massachusetts, and suggested ways for the Legislature to temper the question, should it become law.

While emphasizing that he’s not opposed to legalization in theory, Lewis laid out five reasons why Massachusetts is not ready.

First, the senator said in a State House interview, there has been a “most alarming” decline in young people’s perception of the harm of marijuana. He cited data from a federally funded study. It shows a national drop in the percentage of 12th-graders who think people greatly risk harming themselves physically or in other ways if they smoke marijuana regularly: from 65 percent in 1994 to 36 percent in 2014.


Lewis said that before legalization, there must be a strong and sustained statewide public education campaign that lets young people know marijuana is not safe for them to use.

Second, the state doesn’t have a clear metric or clear protocols for when someone is too impaired by marijuana to drive safely, he said. There is no marijuana equivalent to the legal prohibition of driving with a blood alcohol level of 0.08 or greater. That should change before legalization, to ensure police have the tools to keep the public safe, Lewis posited.

Third, after years of troubled state oversight, Massachusetts has, more or less, just finished implementing a 2012 referendum that legalized marijuana for medical use.

Lewis said the state should “get medical right first,” before legalizing recreational use. The first medical marijuana dispensary opened in June 2015. And while there are six medical dispensaries open now, some have run into supply problems.

Fourth, before legalization, the state should gather detailed baseline data on marijuana use so that changes after legalization could be accurately measured, Lewis said.

And fifth, he said, Massachusetts should wait for federal law to be eased. Marijuana remains prohibited under federal statute, creating a raft of complications for the legal marijuana industry in places like Colorado.


The proposed Massachusetts law would create a “Cannabis Control Commission,” with members appointed by the state treasurer to oversee marijuana stores, cultivation facilities, testing facilities, and manufacturers of edible products like pot-infused cookies.

The measure would impose a 3.75 percent excise tax on retail marijuana sales, in addition to the state’s 6.25 percent sales tax — and it would allow cities and towns to levy an additional 2 percent tax that the municipalities could keep.

One of the ideas behind the measure backed by the Campaign to Regulate Marijuana Like Alcohol in Massachusetts is to create a framework for a regulated and taxed industry to safely blossom.

But Lewis, who described himself as a “Harvard Business School grad and someone who is a capitalist,” said that the incentives of the US economic system don’t work when it comes to a recreational marijuana industry.

“The fiduciary responsibility for a for-profit company is to generate as much profit as possible for a company’s shareholders, whether that’s a private company, for the owners, or whether it’s a public company,” Lewis said.

“The problem is: That is in direct conflict with, overall, what’s best for society in terms of public health and public safety when you’re talking about things like marijuana.”

Lewis argued that the marijuana industry, like the tobacco industry before it, will seek to expand its business by getting new customers and increasing how much product existing customers use — to the detriment of the public good.


The senator floated the idea of other potential systems — setting up state-run shops similar to New Hampshire’s liquor stores, for instance, which he said would not have the same intensity of profit incentive.

Lewis, who is married and has 13- and 16-year-old daughters, said being a father plays into his views:

“Their health, their safety, their happiness — there’s nothing more important.”

And there are signs that Lewis could play a bigger role in the public discussion of the ballot push, which is opposed by major state political figures such as Governor Charlie Baker, Attorney General Maura Healey, and Mayor Martin J. Walsh of Boston.

Baker, a Republican, said in a prepared statement that he is grateful to Lewis and his colleagues for their work on the issue.

“I look forward,” Baker said, “to supporting the senator and others in their public education efforts.”

Joshua Miller can be reached

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