Gideon Castro, 66, was charged with the second-degree murder of Dawn Momohara, a sophomore student who was found dead at a Honolulu high school on March 21, 1977.
Honolulu Police DepartmentDawn Momohara, the 16-year-old girl who was found slain in her Honolulu high school.
In March 1977, a teacher at McKinley High School in Honolulu made a shocking discovery in the school’s English building. Lying deceased and partially clothed on the floor was 16-year-old Dawn Momohara, a sophomore student. She had been strangled and sexually assaulted.
The brutal murder sparked a community-wide panic, but investigators were never able to identify a suspect. The case went cold for nearly 50 years — but now DNA technology has led to an arrest.
Dawn Momohara Is Found Murdered At Her Hawaii High School
On the morning of March 21, 1977, Dawn Momohara was found dead in her Honolulu high school. She was partially undressed and had an orange cloth wrapped tightly around her neck.
Dawn had been reported missing the previous evening when she failed to return home from a shopping trip. Her mother said the teen had received a phone call from an unnamed man on March 20 and then said she was going to meet her friends at a local mall, but it’s unclear if she ever even arrived at the shopping center.
Two witnesses came forward and said they’d seen a suspicious vehicle in the school parking lot the night of March 20, but the leads seemed to end there. Despite canvassing neighborhoods and stopping all cars that matched the description the witnesses provided, the case eventually went cold.
Honolulu Police DepartmentA sketch of the suspect in Momohara’s murder case.
During a press conference, Deena Thoemmes, a lieutenant at the Honolulu Police Department, stated, “Despite following up on numerous leads and interviewing multiple individuals, investigators were unable to identify a suspect at that time.”
Now, thanks to advances in DNA technology, detectives have finally arrested a man believed to be Dawn Momohara’s killer.
DNA Testing Provides Answers Nearly Half A Century Later
In 2019, investigators at the Honolulu Police Department reopened Dawn’s case. This time, investigators built a DNA profile from a semen sample found on Dawn’s shorts.
The police identified two brothers, William and Gideon Castro, as possible matches. They had both attended McKinley High School in the ’70s and had even been interviewed after Dawn’s murder.
At the time, Gideon Castro told police he had met Dawn at a school dance in 1976, the same year he graduated. When asked about the last time he saw her, Castro told authorities that he spoke with her briefly at a carnival in February 1977.
Honolulu Police DepartmentA sketch of the suspect’s car.
In 2023, investigators secretly obtained DNA from the adult children of both Castro brothers. Tests quickly excluded William as the perpetrator, leading investigators to focus on Gideon. When they obtained Gideon’s DNA and tested it against the semen from the shorts, they found it was a match.
With a positive DNA match, authorities arrested the now 66-year-old Gideon Castro at a nursing home in Utah. He has been charged with second-degree murder and is awaiting extradition to Honolulu.
“I want to thank all the individuals and agencies that made today’s arrest possible,” Thoemmes said during the press conference announcing the news. “Thank you all for your dedication and commitment to the tireless pursuit of justice for Dawn and the Momohara family.”
After reading about Dawn Momohara, the 16-year-old girl who was murdered in Hawaii in 1977, go inside the story of Kristin Smart, a college student who was killed by her classmate in 1996. Then, learn about the disappearance of Natalee Holloway while on a graduation trip in Aruba.
