PORTLAND, Maine (AP) — An independent report conducted for a police agency clears the agency’s response to growing concerns about the mental health of a man who later went on to commit the deadliest mass shooting in Maine history, but it does reveal missed opportunities to intervene to prevent the tragedy, legal experts said Friday.

Despite receiving warnings about the man’s deteriorating mental health, drunken threats and possession of guns, the Sagadahoc County Sheriff’s Office avoided confronting Robert Card, the 40-year-old Army reservist who later killed 18 people at a bowling alley and a bar on Oct. 25 in Lewiston, the experts said of the report released late Thursday by Sheriff Joel Merry.

Card’s body was found — with a self-inflicted gunshot wound — two days after the shootings. Reports soon began to emerge that he had spent two weeks in a psychiatric hospital months before the attacks and had amassed weapons.

The legal experts told The Associated Press that the report — prepared for the sheriff’s office by a lawyer who’s a retired federal drug agent— leaves unresolved questions about police’s potential ability to have removed guns from Card before the shootings happened.

The report delved into mental health concerns raised about Card. It states that the response to those concerns by the department’s officers “was reasonable under the totality of the circumstances” at the time. In a statement, Merry said the review “found that responding deputies followed the law and their training with the information available at the time.”

Democratic Gov. Janet Mills has appointed an independent commission led by a former state chief justice to review all aspects of the tragedy. And Maine’s congressional delegation said Friday there will be an independent Army inspector general’s investigation to review the Army’s actions, alongside an ongoing administrative Army investigation.

The Sagadahoc report makes clear that local law enforcement knew Card’s mental health was deteriorating, with reports that he was paranoid, hearing voices, experiencing psychotic episodes and possibly dealing with schizophrenia.

In May, Card’s ex-wife and his son reached out to a school resource officer about what they called Card’s erratic behavior. A deputy worked with the family to get help and heeded its suggestion not to confront Card directly for fear that it could cause an unnecessary escalation, the report states.

In September, police were alerted by officials with the Army Reserves about Card, who was hospitalized in July after exhibiting erratic behavior while training. The officials warned that Card still had access to weapons and that he had threatened to “shoot up” an Army Reserve center in Saco, the report said.

That caught the full attention of police, who responded by briefly staking out the Saco facility and going to Card’s home in Bowdoin, Maine, even as an Army Reserve leader suggested that all that was needed was a “welfare check.”

A visit to Card’s home by Sagadahoc Sgt. Aaron Skolfield on Sept. 16 represented the best opportunity for police to assess Card face-to-face — something that could have been necessary to take him into protective custody, a step needed to trigger Maine’s “yellow flag” law, which allows a judge to temporarily remove someone’s guns during a psychiatric health crisis.

Skolfield called for backup, knowing Card was considered armed and dangerous, and knocked on Card’s door. The deputy saw curtains move and heard noises suggesting Card was inside. But Card did not answer the door, and Skolfield correctly concluded he lacked the legal authority to force the issue during a wellness check, the report said.

Worried for his own safety, Skolfield went back to his cruiser, visited the nearby home of Card’s father and then returned to stake out Card’s home before leaving to respond to a domestic assault, the report said.

All that day, Skolfield was in contact with other law officers, Army officials and family members about Card’s mental health and to ensure that family members were trying to prevent Card’s access to guns.

The report concluded that Skolfield “did not have sufficient grounds to take Mr. Card into protective custody, which also foreclosed his discretion to initiate the process for confiscation of Mr. Card’s firearms.”

No family member or reservist contacted the sheriff’s office after Sept. 17, and a sheriff’s advisory bulletin asking agencies to locate Card was lifted on Oct. 18.

The report’s conclusion that the officers’ actions were reasonable is subject to interpretation, said Adanté Pointer, a civil rights attorney based in Oakland, California, who reviewed the report. What it makes clear is that local law enforcement had numerous opportunities to intercede in “this growing, escalating and ultimately deadly situation” and did not, Pointer said.

The report paints a picture of officers who were “scared” to deal with Card, Pointer said.

There was already enough evidence back in May to begin the process of seizing Card’s weapons under the yellow flag law, said Neama Rahmani, a former federal prosecutor and current president of the West Coast Trial Lawyers in Los Angeles who reviewed the report.

“A different approach to policing, or a different set of laws, might have saved a lot of lives,” Rahmani said.

Prepared by Michael Cunniff, a Portland attorney who is a former supervisory special agent for the U.S. Drug Enforcement Administration, the report also addressed protective custody of those in crisis, the yellow flag law and the temporary seizure of guns.

Cunniff declined comment Friday. Sheriff Merry didn’t immediately respond to questions, including how the report was commissioned and who funded it.

Merry did say his office is cooperating with all investigations.