The Governor’s action on a final suite of gun-control bills has left gun owners in the Pine Tree State with a mixed bag.

Maine Governor Janet Mills (D.) elected to allow LD 2238, which requires a 72-hour waiting period for all gun sales, to become law without her signature on Monday. However, Mills vetoed a separate measure aimed at banning bump stocks. That bill would have amended the state’s ban on machine guns to include any semi-automatic firearm that has been modified “to materially increase its rate of fire.”

Mills’ actions on the two bills provide clarity on the state’s political response to last October’s mass shooting in Lewiston—the deadliest in Maine’s history. They come on the heels of Mills’ signature on her own legislative package last week, which implemented background check requirements for advertised private gun sales and streamlined the process for police to initiate the state’s “yellow flag” confiscation law–a process police failed to use ahead of the attack.

Though the shooting energized gun-control advocates to push for far more aggressive gun-control measures, Mills’ reluctant approach to the final two gun bills highlights the lingering potency of gun-rights concerns in the rural New England state. Those concerns were evident in the Governor’s statements on imposing waiting periods for gun buyers. While she allowed the measure to become law, Mills admitted to being “deeply conflicted” about its constitutionality and potential burden on legal gun owners.

“In carefully considering all the arguments, I have decided to allow this bill to become law,” she said in a statement. “I do so, however, with some caveats and concerns and with the hope that it can be implemented to accomplish its intended goal of preventing suicide by firearm without overburdening our outdoor sports economy and the rights of responsible gun owners and dealers to engage in lawful and constitutionally protected activities.”

She directed the Commissioner of Public Safety and Attorney General to “monitor Constitutional challenges over waiting periods for firearm purchases now playing out in other jurisdictions” and to provide legal guidance to gun owners on how to navigate its requirements in exceptional circumstances, such as temporary transfers or cases in which a person needs a firearm for self-defense in an emergency.

Her decision to veto the bump stock bill resulted from the same concerns. Mills said she sympathized with the bill’s aim to crack down on guns equipped with bump stocks or similar devices. However, she argued its broad definitions risked criminalizing a variety of common semi-automatic firearms and impacting law-abiding gun owners.

“There are a variety of minor modifications that would meet this definition, such as adjusting the trigger weight or changing the buffer spring or bolt in order to increase speed,” she wrote in her veto statement. “These kinds of alterations are common among those using firearms for sporting purposes. The result is that this bill may unintentionally ban a significant number of weapons used for hunting or target shooting by responsible gun owners in Maine.”

Mills’ mixed approach to the two bills drew criticism from both sides of the gun debate. The gun-control group Giffords issued a statement “expressing disappointment” in the Governor over her veto.

“In the months that followed a mass shooting in Lewiston where 18 people were killed, Mainers across the state said enough was enough,” Emma Brown, the group’s Executive Director, said. “But Governor Janet Mills fell short by vetoing a ban on devices that turn semi-automatic rifles into machine guns. Machine guns have no place on the streets of Maine.”

Meanwhile, state gun-rights groups, including Sportsman’s Alliance of Maine and Gun Owners of Maine, announced they were planning to file a lawsuit against the waiting period mandate to prevent it from taking effect.

“The constitution both in the state of Maine and the United States has codified our inalienable right to bear arms,” Laura Whitcomb, president of Gun Owners of Maine, told the Portland Press Herald. “When you put somebody through the paces of having a background check, and they’ve been found to be a law-abiding citizen who is legally allowed to have a firearm, and then you give them an arbitrary waiting period that infringes on those constitutional rights. … We don’t do that with any of our other rights.”

Unless the activists win an early injunction to block it, the waiting period requirement will take effect 90 days after the legislature officially adjourns.