BOSTON >> The statewide officeholder who would oversee a legalized marijuana industry in Massachusetts says the excise tax rate on cannabis needs to be much higher — as much as 10 times — than what is proposed in the ballot question voters will decide on Nov. 8.

Question 4 on the November ballot would legalize and regulate marijuana in Massachusetts, and would set an excise tax rate of 3.75 percent on all marijuana sales, a rate state Treasurer Deborah Goldberg called "actually quite low" at a Greater Boston Chamber of Commerce breakfast.

"Even if you roll in our 6.25 percent sales tax and a potential 2 percent local option tax — on top of the 3.75 — Massachusetts would pale in comparison to other states," Goldberg said, citing excise tax rates of 29 percent in Colorado, 37 percent in Washington, and 25 percent in Alaska and Oregon.

"There's something wrong with this revenue picture," she said.

Legal cannabis supporters say the tax rate should be kept low enough to suppress the black market. If the rate is too high, supporters say, many marijuana users would continue to buy the drug from the tax-free black market, an argument Goldberg said "didn't make a lot of sense to me."

Asked Wednesday about her preference for the marijuana excise tax rate, Goldberg said, "The higher the better."

Revenues from the proposed 3.75 percent excise tax may not be enough to cover the costs of implementing a legal marijuana industry in the state, the treasurer said, and she suggested that Massachusetts ought to tax the plant at a rate closer to Washington's 37 percent.


"I suspect that the actual revenue will not impact our bottom line in a significant way, whereas I looked at some of the numbers for the first six months in Washington state and I went, 'now that is revenue,'" she said. "So something in the middle makes sense."

Yes on 4, the group pushing for the question's passage, estimates that the tax structure in its ballot question will generate $100 million in annual revenue. For comparison, Washington state collected $128,948,915 in marijuana excise taxes last year, according to data from the Washington State Liquor and Cannabis Board.