Suspect pleads not guilty in 1975 slaying

A man recently charged in the 1975 slaying of his childhood neighbor pleaded not guilty this morning in King County Superior Court.

James Groth, 49, was charged late last month with first-degree murder in the fatal stabbing of 16-year-old Diana Peterson in the backyard of her Richmond Beach home in February 1975.

Groth, who was 16 at the time of the slaying, was interviewed immediately after the slaying. He also failed a polygraph test shortly thereafter, and another in May 2006.

King County sheriff's spokesman John Urquhart attributed the murder charge to more than a year of work by a new batch of detectives and prosecutors. He said there was no DNA link that led them to believe Groth is responsible for the slaying.

When cold-case detectives picked the case up in 2006, Groth was a person of interest. Urquhart said Groth denied any involvement until detectives spoke with him again late last month.

During this most recent interview, he didn't deny any connection with Peterson's death, court papers said. He said that he and Peterson fought physically just before her death but said it wasn't unusual since they would often "tussle," court papers said.

Groth and Peterson were classmates at the former Shoreline High School.

Peterson's family packed a downtown Seattle courtroom this morning to catch a glimpse of Groth.

Leanne Peterson, the slain girl's mother, said the stocky, balding man looks nothing like the "big hair" teenager who used to live near their home. She said that she never believed authorities would make an arrest in her daughter's death.

"This is something we never thought would happen. We are grateful for the cold case people," Leanne Peterson said as she walked out of the courtroom surrounded by several of her eight children and other relatives.

Leanne Peterson said she is hopeful that Groth pleads guilty so that she doesn't have to "go through the emotions."

Jennifer Sullivan: 206-464-8294 or jensullivan@seattletimes.com