For two years, Isaac Barnes became increasingly paranoid.
He spoke of people who wanted to “get him” and sought isolation in the woods when not in his bedroom in Boone, N.C.
“He didn’t even talk to us at a certain point about how he was feeling,” said his older sister, Sommer Barnes. “We all felt so helpless.”
Last month, when Mr. Barnes, 32, received a routine summons to appear for jury duty, he panicked. He fled into the forest, then returned to his mother’s home a few days later.
By midmorning on April 28, he was barricaded there in the course of a 13-hour standoff with the police. His mother and stepfather, Michelle and George Ligon, and two sheriff’s deputies, Sgt. Chris Ward and Deputy Logan Fox, had been killed.
The police said the deputies were shot before the standoff, as they descended basement stairs to check on Mr. Ligon’s welfare after his employer had called to report his absence. The authorities have not said when the Ligons were killed or how Mr. Barnes died.
Ms. Barnes said she wanted to talk about her brother’s case because her family had spent days warning officials that he was becoming more and more troubled, and she questions how seriously the police took the threat that his mental state posed.
“The message being portrayed is that this was an unavoidable tragedy,” Ms. Barnes said. “That’s not really true. There were things that could have been done to protect at least the deputies. That’s where my mind keeps landing.”
The Watauga County Sheriff’s Office declined to comment. A spokeswoman for the North Carolina State Bureau of Investigation said the agency was investigating the shootings.
Last week, the bodies of Deputy Fox, 25, and Sergeant Ward, 36, were carried on horse-drawn carriages through the streets of Boone, a city of about 20,000 people that overlooks the Blue Ridge Mountains.
On Monday, the town asked residents to put a blue bulb in their porch light to honor the two men and to wear a red ribbon for Ms. Ligon, who worked for the county’s tourism development authority, and Mr. Ligon, a branch manager at Terminix.
“Most of us all know each other,” said John A. Ward III, the town manager. “The officers were well known. They both went to school here. They were from here, they were friends with the cops in town. It was an extremely big hit just due to how familiar everyone was with each other.”
Chief Andy Le Beau of the Boone Police Department, whose officers responded as backup during the standoff, said Mr. Barnes’s case underscored the challenge towns face when confronted with families struggling to get their loved ones help.
“That’s a nationwide question bigger than little old Boone P.D.,” he said. “I don’t know that anything could have been done to avoid this situation other than him getting mental health treatment earlier on.”
Ms. Barnes, 34, said her family struggled to help her brother, who resisted calls to see a doctor and never received a formal diagnosis. He had been living with his mother and stepfather for two years his sister said.
“They were really compassionate and empathetic people and they knew he was hurting terribly so they welcomed him back home,” said Kathy Beach, the pastor at Rumple Memorial Presbyterian Church in Blowing Rock, N.C., where George Ligon had been a longtime member.
Mr. Barnes had once worked in landscaping but stopped after he developed a herniated disk, and became reclusive, his sister said. He stopped seeing friends and seldom left his room except to escape to the woods near his father’s house in Avery County, she said.
Ms. Barnes said the last time they spoke was a year ago, when she told him she was worried about him.
“That’s as far as I got,” she said.
He saw calls to see a doctor for mental health treatment, or even for a physical condition, “as some sort of nefarious force trying to control his mind,” Ms. Barnes said.
Ms. Barnes texted frequently with her mother, who gave her updates about him.
His condition seemed to worsen after his dog died in late March.
“We were all really concerned that that would do something to shake up his mental health,” Ms. Barnes said.
It was around that time that Mr. Barnes, who had never been violent, shoved his mother and said, “You better not talk to me,” Ms. Barnes said.
Then the jury summons came. He fled, took his mother’s debit card and stole $600, Ms. Barnes said.
While he was in the woods, his car broke down and he called his father, Joseph Barnes, for help, Ms. Barnes said.
The elder Mr. Barnes took out a tool when he arrived, at which point his son accused him of trying to attack and pulled out a knife, Ms. Barnes said.
Joseph Barnes fled and called the Avery County Sheriff’s Office to tell them his son was behaving erratically and to be careful if they saw him.
It is unclear what kind of communication occurred between the Avery and Watauga sheriff’s departments. Officials in Avery County did not respond to requests for comment.
Ms. Barnes said that late on April 27, the day before the shootings, her father went to the Watauga magistrate’s office to file a report about his son. Ms. Barnes said her father was looking for help, possibly by having his son committed.
Mr. Barnes declined to be interviewed, and the magistrate did not respond to requests for comment.
Sheriff Len Hagaman of Watauga County has told reporters that his department had received calls on Sunday, three days before the shooting, from “concerned folks that know him.”
“They were just trying to give us a heads-up, this is what he’s thinking about doing and for us to be careful,” Sheriff Hagaman said.
“It was a welfare check,” he said. “You don’t expect things to be like this. We do that every day.”
In an interview with The Associated Press, Sheriff Hagaman said that the Ligons contacted his department the day before the standoff and said they were concerned about Mr. Barnes.
Welfare checks can be dangerous and unpredictable, and officers need as much information as possible heading into them, said Chuck Wexler, the executive director of the Police Executive Research Forum, an organization that provides recommendations for police departments.
Officers can be taught “to slow things down and use time and distance and cover,” he said. “But then you have a situation like this, which unfolds very quickly and officers attempt to intervene, then wind up dying in the process.”
Sheriff Hagaman told The Associated Press that deputies went to the woods to look for Mr. Barnes after the confrontation with his father, but did not find him. He said they did not expect Mr. Barnes to be at the Ligons’ house on April 28.
Ms. Barnes said her brother’s driver’s license listed his mother’s address.
She said that her mother and stepfather did not keep guns in the house and that she still did not know how her brother obtained firearms.
And she said she had asked herself repeatedly if the deputies were warned that her brother could be in the house and in the throes of a mental health breakdown.
“This shouldn’t have been treated as an everyday wellness check,” she said.