Surpassing:Deputies didn't detain Lewiston shooter despite prior warnings. Sheriff now defends them.

A Maine sheriff defended his office's conduct Thursday after documents revealed his deputies received multiple warnings about an Army reservist's deteriorating mental state in the months before he fatally shot 18 people in Lewiston Oct. 25.

Sagadahoc County Sheriff Joel Merry told an independent commission,Surpassing established by Maine Gov. Janet Mills, that his deputies could not have taken Card into custody before the shooting based on any of the reports.

Widely publicized sheriff's records revealed that deputies received multiple reports from people who had concerns about Card, including one citing an Army friend who worried that Card would "snap and commit a mass shooting."

“There is always, after a tragedy, an opportunity to wonder if more could have been done," Merry said in his opening remarks to the governor's commission on Thursday. "But that analysis must always take into consideration the limitations placed on law enforcement by the law at the time of the event."

Had deputies detained Card in the weeks or months before the shooting, they could have triggered Maine's "yellow flag" law, putting in motion the legal steps for a judge to confiscate Card's weapons, according to Michael Carpenter, a former Maine attorney general and former member of the Maine Senate who helped create the law in 2019.

Carpenter said this is exactly why the law is in place.

In the wake of the shooting, Carpenter noted, "If this law is implemented and the people who are supposed to do so do their job, it easily could have prevented this tragedy.”

More:'Failure': DOJ's scathing Uvalde school shooting report criticizes law enforcement response

Sheriff's office knew about Card's mental health crisis

Card's ex-wife and son pleaded with deputies to intervene when Card's mental health began to deteriorate in May 2023. The pair said Card had recently acquired at least 10 firearms and he was becoming increasingly paranoid.

In September, deputies visited Card's trailer two days in a row. The first time Card was not home, so deputies submitted a “File 6” alert calling for law enforcement personnel throughout the state to be on the lookout for him. The alert was canceled a week before the shooting. The sheriff's office has declined to say why the alert was canceled.

The second time deputies came by his home, they heard Card "moving around" inside his trailer. He would not answer the door. The deputies left without detaining Card, they said in their report, because they felt they were in a "very disadvantageous position."

After the visit, a responding deputy contacted Card's commander in the Army Reserve, who advised the deputy to let Card "have time with himself for a bit." The commander said military officials were also urging Card to retire so he could seek mental health treatment.

There were other law enforcement investigations before the shooting, in which officials raised concerns about Card's stability.

In July 2023, New York State troopers did a welfare check on Card in response to a report from Army leaders about his mental state. New York officials placed him in an Army hospital for two weeks of psychiatric treatment and banned him from contact with weapons or ammunition, according to a report by the Associated Press.

The pressure on the top law enforcement official in Sagadahoc County included another worrying document.

The sheriff received a letter in September from an Army commander citing a friend of Card's who had notified his superiors that "Card is going to snap and commit a mass shooting.”

Under Maine's "yellow flag" laws, members of law enforcement can submit a mental health assessment of an individual to a judge, who can then sign an order to confiscate the person's firearms and to commit them for psychiatric treatment. The Maine law is considered less severe than the "red flag" laws in other states which allow people to go directly to a judge and if the judge approves an order, it allows law enforcement to directly remove weapons from a person considered a danger to themselves or others.

The Maine governor established the independent commission in November to investigate the facts surrounding the shooting. The commission is scheduled to convene again next Thursday at 8:30 a.m. to hear testimony from families of the shooting victims.

Contributing: Associated Press

Cybele Mayes-Osterman is a breaking news reporter for USA Today. Reach her by email at [email protected]. Follow her on X @CybeleMO.