Beacon Hill is abuzz over what changes might be made to the voter-passed law legalizing the recreational use of marijuana. Lawmakers, who opted not to take up legalization via legislation, are now considering how the law can be tweaked.

Still to be determined is exactly what constitutes a tweak, and what would be a major change.

Marijuana will be one of the dominant topics of discussion in the new legislative session, which gets underway on Jan. 4. When retail sales of marijuana can begin, when retail licenses can be issued, taxation rates and other aspects of the law all could be changed by the Legislature in the upcoming session. Closed-door meetings are taking place between stakeholders and lawmakers to discuss possible changes.

As we get closer to the law going into effect — and as the Legislature takes up the issue — here are three things to watch for that could delay or alter the law.

Certification

There is a slight possibility the law won’t take effect on Dec. 15, as spelled out in the referendum. That’s because the election results aren't certified yet.

While election day was Nov. 8, and pretty much all results were known by the next morning, the results are not official until certified by the Governor’s Council. The certification process is required by law, and is usually finished by mid-December.

Since this is a presidential election year, the results for president must be completed first, so that the electors can meet at the State House on Dec. 19 to cast their ballots. Next, the secretary of state’s office sets out to verify the results for the congressional races (even though most of the candidates were unopposed). That certification has to be sent to Washington by Dec. 16. Legislative and other races are then certified, as are the ballot questions. For the elected officials, they don’t get sworn in to their new terms until January, which has always been plenty of time for the results to be certified.

For the marijuana referendum, the secretary of state’s office says it will be certified, but can’t guarantee it will ready before Dec. 14, the last scheduled date for the Governor’s Council to meet before the law takes effect. The council could choose to come in for a special session to get it done, or choose to wait until their next scheduled meeting on Dec. 21.

Start Date/Home Grow

While the law is scheduled to take effect Dec. 15, it will still be another 12 and a half months before the first retail dispensary can open in Massachusetts -- barring any delays that could be imposed by the Legislature.

But residents will be able to begin growing up to six cannabis plants per person (maximum 12 per household) right away, and there are concerns about that. Homegrown plants would not be subject to any tax. And state Treasurer Deborah Goldberg has questioned whether homegrown should be allowed, instead requiring those who want to consume marijuana purchase taxable product from a licensed retail dispensary.

There’s a slight chance lawmakers could decide to delay the effective date, and to that end, home growing. Since the Legislature ended formal sessions July 31, lawmakers would have to take up the question of a delay during one of their routine, sparsely attended informal sessions. Items taken up during an informal session are normally noncontroversial, and require unanimous consent to even be brought up.

"Everything is on the table," Senate President Stan Rosenberg said Monday when asked if legislators are considering delaying the Dec. 15 start date. But he added there's a strong feeling lawmakers should be looking at later deadlines, rather than the earlier one.

House Speaker Robert DeLeo also strongly indicated delaying the start date would be unlikely.

"Whether we would delay the Dec. 15 [start date], I think that would probably be a little more difficult shall we say to delay," DeLeo said.

Tax Rate

One of the aspects of the new law likely to be scrutinized by lawmakers in the 2017 session is the tax rate for marijuana products purchased at retail dispensaries.

The tax rate as set by the referendum is low, compared with the rate in states where recreational marijuana is already legal.

The Massachusetts referendum levies an excise tax of 3.75 percent of the total sales price received by the marijuana retailer. Communities can impose a local sales tax of up to 2 percent. So with the state’s 6.25 percent sales tax, the maximum tax on marijuana would be 12 percent. Combined taxes on marijuana in Colorado are roughly 29 percent. In Washington State, the rate is even higher: 37 percent.

Massachusetts lawmakers could decide to increase the tax, to make sure enough is brought in to pay for the administration and enforcement of the law by the soon-to-be-named Cannabis Control Commission.

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