Carol Paulson thought the worst was surely behind her.

Her daughter, Katherine, after years of struggling with mental illness, had moved with her from Massachusetts to Kennebunk in 2009 and become a wonderful companion.

A caring and generous soul, Katherine Paulson attended to her mother after she developed a heart condition and bleeding ulcers. She also looked after her grandmother – now 100.

But in early 2011, Carol began to worry about her 39-year-old daughter, who had stopped taking her medications and become increasingly quiet and moody. She and her daughter’s counselor were concerned, and they discussed strategies to get her back on her medication.

One of the options was for Carol to call police and have her daughter involuntarily committed to a hospital, so she would have to take medications.

That’s what Carol resolved to do on the night of March 27, 2011. But 19 seconds after police arrived at her door, her daughter had been shot dead.

After reviewing the circumstances of the encounter in Paulson’s home, the Maine Attorney General’s Office, which investigates all police shootings, concluded that the shooting was justified.

Carol and James Paulson adopted Katherine from an Alaskan Eskimo family in Nome, where a relative had been doing anthropological work. Most of the babies in the Nome nursery were sick, and the Paulsons arranged to have their new daughter flown to Anchorage and then to the East Coast. She arrived in Boston weighing just 4 pounds at 2 weeks old.

Katherine was a determined child growing up. She was intent on performing well as an equestrian and could swim at age 2. She made friends easily.

When she was in middle school, she began showing signs of mental illness. When her parents went through a bitter divorce, she was hospitalized and at times forcibly restrained, said Greg Bogojavlensky, her biological brother.

Katherine Paulson was diagnosed with bipolar disorder, paranoid schizophrenia, obsessive compulsive disorder and attention deficit-hyperactivity disorder, he said.

She had two runs-ins with the law, which led to charges of assault and battery with a dangerous weapon, assault and battery on a police officer, and disorderly conduct, as well as episodes where she was taken into protective custody.

Katherine Paulson lived with her father after her parents’ divorce, but when he retired and moved to the West Coast a few years ago, she moved in with her mother and grandmother.

“Things were working out well there for all three of them, and Kate did not have any psychological episodes or trouble with the law of any kind,” said her brother.

But last spring, Carol Paulson became worried about her daughter, who was refusing to take her medication. “There was nothing violent, nothing that I can put my finger on, but I could just tell something was going on,” she said.

One night she called 911 and told police that she and her daughter had had a dispute, and that she was concerned for her own safety. Paulson told the dispatcher that her daughter had psychological problems, and she referred to a recent conversation with a crisis worker, according to a report on the shooting incident by the Attorney General’s Office.

Kennebunk police Sgt. Juliet Gilman and Officer Joshua Morneau responded to the call.

Morneau approached Katherine Paulson in the kitchen, with Carol Paulson sitting 10 feet away in the living room, speaking with Gilman and unable to see the interaction.

“Katy was blocked. She was in the kitchen, on the far wall. … If I had an officer coming at me with a gun, I might pick up a weapon,” Carol Paulson said.

The attorney general’s report said Morneau was introducing himself when Katherine Paulson grabbed a kitchen knife with an 8-inch blade and advanced on him. He couldn’t back up because of “a physical obstruction,” the report says, and drew his gun and fired four shots after she refused several orders to drop the knife.

The attorney general concluded that Morneau, who was not told about Katherine Paulson’s psychological problems by the 911 dispatcher, reasonably feared for his life. In his statement to investigators, the officer said, “I thought she was coming for me. I was scared.”

A separate, administrative review of the incident found that Paulson was too close to Morneau for him to use others types of force, including a Taser. It determined that the department’s policies were adhered to and that training was adequate.Lt. Anthony Bean Burpee said after the shooting that the police response could have been different if the officers had known about Katherine Paulson’s mental illness.

Paulson said she still cannot bring herself to go through the photo album containing pictures of her daughter.

“My life has been destroyed because of what happened that night,” she said in a March interview. “It’s hard for me to put one foot in front of the other foot, even though it’s almost a year.”