Andrew Sumner, a Folsom man who faced second-degree murder charges in the 2012 stabbing death of a Slidell woman, pleaded guilty Monday to manslaughter, aggravated arson and obstruction of justice.

Sumner, now 22, was one of three people implicated in the death of 32-year-old Ashley King, who was stabbed multiple times before her body was burned in her Slidell apartment.

The others were Devin Baham, 24, and Katelyn Marie Lusich, who was pregnant with Sumner’s child at the time of the crime and is now his wife.

According to police, Lusich drove Baham and Sumner to King’s apartment on Bayou Lane in February 2012 to rob her of drugs and money. But the men allegedly emerged saying the robbery had gone awry and King had been stabbed to death. The two men allegedly returned to the apartment the next day to set it on fire, using gasoline siphoned from a boat. The fire destroyed a large part of the apartment.

Both Sumner and Lusich made plea deals with the 22nd Judicial District Attorney’s Office in exchange for testifying against Baham, who is scheduled to go on trial April 6 on charges of second-degree murder, aggravated arson and obstruction of justice.

Sumner’s sentencing has not been scheduled, pending Baham’s trial. Judge Allison Penzato said she will hold a status hearing June 24 to determine whether to proceed with the sentencing.

Lusich pleaded guilty in September to obstruction of justice. The additional counts against her of second-degree murder and aggravated arson will be dropped once she testifies.

Lusich, who was 17 at the time of King’s death, was sentenced to 40 years after her plea, but her attorney, Rachel Yazbeck, said at the time that she is expected to serve about 13 years.

Dwight Doskey, Sumner’s attorney, said his client faces up to 100 years in prison. Manslaughter and obstruction of justice both carry a maximum of 40 years and aggravated arson a maximum of 20 years. How much time he will actually serve depends on his cooperation in the prosecution of Baham, Doskey said.

Assistant District Attorney Julie Knight is prosecuting the cases.

Initially, Lusich was charged as an accessory after the fact to first-degree murder and armed robbery, and Baham and Sumner faced first-degree murder charges. But in May 2013, a grand jury reindicted all three on the same charges: second-degree murder, aggravated arson and obstruction of justice.

The victim’s father, Joseph King, was in the courtroom Monday, sitting stoically as Sumner appeared before the judge in prison stripes and shackles, answering questions about whether he understood the charges to which he was pleading guilty and the rights he was waiving.

The judge asked Sumner if he was pleading guilty “because you in truth and in fact committed these crimes.”

“Yes, your honor,” he said.

But King, who trains race horses, became tearful later as he talked about his daughter, who had moved to Slidell from Louisville, Kentucky, to be closer to him. He said she was getting her life on track with plans to marry and start a tanning-salon business.

His daughter could be overly trusting, he said, and he had a bad feeling about some of the people she had met. He said he had begged her to go with him to Lafayette to see some horses the day before she was murdered, but she didn’t want to go.

King, who said he has been to court 21 times, met Sumner’s father, who approached him after the proceedings. “He told me everyone loses,” King said.

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