The verdict means Laura Sorensen will be sent to Western State Hospital, perhaps for the rest of her life, The News Tribune reported.
According to court documents, Sorensen thought she was hunting pedophiles when she walked into the Peninsula Market near Gig Harbor, and shot the three men.
David Long of Wauna died three months after he was shot.
Multiple psychological evaluations conducted by Western State psychologists found Sorensen has been suffering from a "severe, persistent mental disorder" that probably started in her childhood. The evaluations found she posed a high risk of danger to others.
Deputy Prosecutor Lori Kooiman said the decision to accept an insanity defense was rare and difficult.
"It is not a decision that the state takes lightly," Kooiman said. "If there ever was a case that was an insanity defense, this was it. Western State will not be a resort. Her prognosis for ever getting released is very, very slim."
"My brother was one in a million," David Long's sister, Heidi Michaelson, said as she read a statement to the court. "He was a hard worker. He taught himself how to play the guitar, how to ride a horse, how to rope cows. He never got to have a child. He never got to find the love of his life."
Court documents show Sorensen was hospitalized as a suicide risk as a teen and diagnosed with schizophrenia. She tried to stab her stepfather. At 19, while living in an apartment in Gig Harbor, she began to think her neighbor's apartment was a "den of iniquity," and tried to set it on fire, court records say.
Lee Crider also spoke. Sorensen shot him in the leg that day in the grocery. He walked to the bench aided by a cane.
"Sympathy doesn't negate the fact that she walked into that grocery store and absolutely knew what she was doing wasn't right," he said.
Sorensen's mother, Jennifer Sorensen, said after the shootings that the family had tried repeatedly to obtain treatment for her daughter.
"There have been times in recent years that our family has begged for (Laura) to be committed yet again, with no response," Jennifer Sorensen said Thursday in a statement. "Please know that we have tried to do our best for Laura with the resources we had available to us."
Sorensen herself spoke last.
"I would like to apologize for my actions," she said. "I understand that he (David Long) was a good person and by far did not deserve this. I also understand that nothing I say will bring him back."
Information from: The News Tribune, http://www.thenewstribune.com
More Northwest Headlines
Injured Washington firefighter’s condition upgraded Teacher contracts still being negotiated across Washington 1:57 p.m. Eastern Oregon fire destroys 2 more homes, guest house 1:57 p.m. Lakewood dedicating school in memory of 4 slain officers 1:57 p.m. Wildfires in northern Idaho lead to evacuation warnings 1:57 p.m. Police: Oregon shooting victim lured to his death 1:57 p.m. 50-foot tree falls in Kelso, narrowly avoiding homeowner 1:57 p.m. Strong winds blamed for 2 deaths in Puget Sound area
Our new comment system is not supported in IE 7. Please upgrade your browser here.