Six days before a Seattle woman was stabbed to death in her home, a judge declined to have the suspect locked up.

Isaiah M.K. Kalebu, a 23-year-old man with a history of mental illness, was arrested in the stabbing Friday night and was scheduled to have a bail hearing at the King County Jail on Saturday afternoon.

Earlier this month, he was out on bail pending trial on charges that he threatened to kill his mother last year. After a suspicious fire at his aunt's home killed two people, prosecutors asked King County Superior Court Judge Brian Gain to remand Kalebu to custody.

The fire occurred July 9, one day after the aunt, Rachel Kalebu, filed for a protection order against him.

According to court documents cited by The Seattle Times, Deputy King County Prosecutor Zac Hostetter said his request was "based on concerns of mental instability and Rachel Kalebu's protection order filed just prior to the arson."

Hostetter also noted that Kalebu had missed an earlier court date. The judge, however, declined to jail Kalebu.

Six days later, on July 19, investigators say Kalebu crawled through an open window at a home in Seattle's South Park neighborhood and stabbed 39-year-old Teresa Butz to death. Her partner was injured in the attack.

Kalebu was arrested Friday after police released surveillance video showing him with his pit bull and a Metro bus driver spotted him with the dog near Seattle's Magnuson Park. Authorities declined to say what evidence linked him to the stabbing.

He remains the only person of interest in the fatal July 9 fire at his aunt's home in University Place, but authorities have been awaiting lab results in the case.

"When we saw the video of the suspect with the pit bull, all of our hearts down here skipped a beat," said Sgt. Ed Troyer of the Pierce County sheriff's office, which is investigating the fire. "Unfortunately, we didn't have enough to arrest him."

The harassment charges Kalebu faces stem from a March 2008 incident in which he is accused of threatening his mother after she confronted him about not taking prescribed medication for "bipolar and manic-depressive" conditions.

Kalebu told his mother, "Enjoy your last day on earth," and left the house, only to return the next day and throw a large rock through the windshield of her car, a police affidavit said.

After his arrest, a state psychologist evaluated Kalebu at Western State Hospital. The evaluation found he "did not have the capacity to rationally understand" the case against him.

Butz is the sister of the Tony-winning Broadway star Nobert Leo Butz, who has a lead role in the new musical "Catch Me If You Can" based on the 2002 Steven Spielberg film starring Leonardo DiCaprio and Tom Hanks. Preview performances of the musical at Seattle's 5th Avenue Theatre were canceled after the slaying. The performances are scheduled to resume Tuesday.

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