Schoolmate arrested girl’s 1977 killing returning to Hawaii to face murder charge

A 66-year-old suspect in the 1977 slaying of a Hawaii teenager agreed on Wednesday to be extradited from Utah to face a murder charge.

Gideon Castro waived the right to challenge his extradition during a hearing before a judge in Salt Lake City. Castro, who is ill, appeared by video from a hospital bed.

“He intends to fight the charges. But he agrees to be extradited to fight the charges in Hawaii,” said defense attorney Marlene Mohn.

On March 21, 1977, shortly after 7:30 a.m., Honolulu police found the body of 16-year-old Dawn Momohara on the second floor of a school building. She was lying on her back, partially clothed with an orange cloth wrapped tightly around her neck and had been sexually assaulted and strangled, police said.

Police used advances in DNA technology to connect Castro to the killing. They had interviewed Castro and his brother in 1977. But they were unable to conclusively link Castro to the killing until obtaining DNA samples in recent years.

The morning before Momohara was killed, she got a call from an unknown male and told her mother she was going to a nearby shopping center with friends. That was the last time her mother saw her, police said.

Police released sketches of a person of interest and a possible vehicle described by witnesses as a 1974 or 1975 Pontiac Lemans. A witness reported seeing the car when he and his girlfriend drove through campus the night before Momohara died. The witness saw a man and the car on the grass near the school’s English building, police said.

In 2019, cold case detectives asked a forensic biology unit to examine several items of evidence from the scene, including Momohara’s underwear. They were able to develop a DNA profile in 2020. Then, in 2023, police received information about potential suspects, two brothers who were interviewed in 1977.

Several days after Momohara was killed, detectives interviewed Castro, who graduated from McKinley High in 1976. He said he met Momohara at a school dance that year and last saw her at a carnival on campus in February 1977. Police interviewed his brother, who also met Momohara at the dance

In November 2023, Honolulu police went to Chicago, where the brother was living. They “surreptitiously” obtained DNA from one of the brother’s adult children, police said.

Lab findings excluded the brother as a suspect, but a DNA sample from Castro’s adult son, and later from Castro himself, proved he was responsible, police said.

Castro was arrested last month at the nursing home where he had been living in Millcreek, just south of Salt Lake City, on a fugitive warrant for suspicion of second-degree murder. Jail records indicate he is still a resident of Hawaii, and it is unclear how long he had been living in Utah.