It’s been a year since the deadliest mass shooting in Maine.

Investigations into the tragedy have revealed ways in which law enforcement could have tried to prevent the gunman from killing 18 people and wounding 13 others in Lewiston.

Law enforcement and lawmakers alike say states should heed those lessons. Maine and Massachusetts already have. But the extent of gun laws — and recent gun law reforms — in the neighboring states differs.

“The shooting incident that occurred in Lewiston could happen anywhere,” said Tom Nolan, a former police lieutenant with the Boston Police Department, and criminal justice professor. “It could happen in Massachusetts, although we do have more restrictive gun licensing laws here in Massachusetts than they do in Maine.”

A recent review from the New England State Police Administrators Conference recommended legislative review of extreme risk protection orders, commonly called “yellow flag” or “red flag” laws, which allow authorities to temporarily seize firearms from someone deemed a danger to themselves or others.

The report pointed to the weakness of Maine’s yellow flag law. At the time of the shooting, Maine law required police meet face-to-face with someone before initiating the process to seize their firearms. Police would then have to obtain a mental health evaluation and a judge’s order to remove weapons.

“That kind of came apart at the seams,” said Nolan, “because law enforcement was reluctant to invoke that process because of complaints about the cumbersome nature of the paperwork process.”

In the case of Lewiston, police said they attempted to implement the yellow flag law but could not do so because the gunman refused to answer his door. Maine lawmakers have since amended the law to allow police to go directly to a judge for a warrant.

Some gun reform advocates want the state to adopt a red flag law, which typically allow concerned family members to directly petition a judge for firearm seizures instead of going through police.

Massachusetts already had a red flag law, and it was recently beefed up.

Gov. Maura Healey used executive power this summer to put a new gun law into effect that, among other reforms, expanded the definition of who can go to court and request an extreme risk protection order. Previously, only a family member or police could request that. Now, health care providers and school officials also have the ability.

“I think that gives us some extra eyes and another level of protection. If somebody is having a severe mental health issue and they become a danger, we can take some action,” said Michael Bradley, a retired police chief and current executive director of the Massachusetts Chiefs of Police Association.

Massachusetts’ new gun law also includes regulation of so-called “ghost guns,” bans firearms from schools and polling places, and “reinforces some of the authority that police chiefs have as being able to issue licenses, revoke or suspend licenses as well,” said Bradley.

He said in this state, a gun license can be denied, suspended and revoked based on suitability. That means if the individual has mental health issues and are deemed a threat to public safety, police have the ability to suspend the license and seize the firearm. An appeal process is available to the individual.

An older law also requires that people taken into custody for a mental health issue, and sent to a hospital for involuntary hospitalization have their information entered into a database. That alerts the licensing authority from whichever municipality to see that someone they’ve issued a license to was hospitalized. From there, Bradley said, law enforcement can get details about the incident and make a decision about “suitability.”

Maine had a similar law in place that could have alerted authorities to the Lewiston gunman’s behavior. But the state’s law only requires reporting for court-ordered involuntary hospital stays, and the gunman’s hospitalization came at the direction of his Army Reserve captain.

“I think some of the problem was the result of his involvement with with the military, National Guard and the military system,” said Dennis Galvin, president of the Massachusetts Association for Professional Law Enforcement. “Sometimes when you cross over into an area where you’ve got the military, they don’t necessarily share their information like they would normally in a civilian format.”

As Galvin reflected on the Lewiston shooting and the shortcomings it made clear, he said it’s important to keep laws current.

“We’re having discussions in our own organization looking at the laws regarding mental illness to see, you know, are they up to speed? Do they reflect reality, or are they outdated or what?” he said.