BOSTON (AP) — Massachusetts Gov. Charlie Baker signed a bill Friday aimed at delaying by up to six months the opening of marijuana shops in the state until mid-2018.

An aide to the Republican governor said Baker shares the desire of state lawmakers to thoroughly prepare for the launch of a new industry distributing a controlled substance.

Baker is “committed to adhering to the will of the voters by implementing the new law as effectively and responsibly as possible,” the governor’s communications director Lizzy Guyton said.

Baker’s decision to sign the bill came as a small group of marijuana activists protested outside the Statehouse.

Members of the Massachusetts Cannabis Reform Coalition and the National Organization for the Reform of Marijuana Laws faulted lawmakers for passing the bill during end-of-year sessions and said the delay “flies in the face of the will of the voters” who approved the ballot question legalizing pot.

The House and Senate passed the bill Wednesday without a public hearing and without debate during informal sessions in both chambers. Only a handful of lawmakers were present.

The ballot initiative that allows adults 21 and over to possess and use limited amounts of recreational marijuana and grow as many as a dozen pot plants in their homes was approved by 53.7 percent of voters on Nov. 8 and took effect Dec. 15.

The action by lawmakers doesn’t change that. But what it’s almost certain to do is push back the timetable for opening retail marijuana stores from the beginning of 2018 until the middle of that year.

Senate President Stan Rosenberg and House Speaker Robert DeLeo, both Democrats, said pushing back the deadlines will give lawmakers more time improve the law by considering issues that were not addressed in the ballot question.

RachelRamone Donlan was among the dozen or so protesters outside the Statehouse. The 45-year-old Braintree resident said she and other cannabis activists are “100 percent outraged” that a small group of lawmakers undid the will of the people. She said she’s even angrier that Baker signed the bill.

Donlan also warned of what she called a legal gray area that will confuse people.

“We are in fear that people are going to get arrested in the next six months because there will be a time frame when it’s legal to possess it but you cannot buy it,” Donlan said. “We’re losing out on tax revenue and we’re fueling the black market.”

Among the key deadlines that would be put off six months include the current March 1 deadline for state Treasurer Deb Goldberg to appoint a cannabis control commission to oversee the recreational marijuana market; a Sept. 15 deadline for the commission to approve detailed regulations; an Oct. 1 deadline for accepting applications for retail marijuana outlets, and the Jan. 1, 2018, deadline for licensing the first pot shops.

For now, it remains illegal in Massachusetts to sell pot except to registered medical marijuana patients.