GREELEY, Colo. (CBS4) – Advances in DNA technology helped lead Weld County investigators to a suspect in a murder dating back more than 41 years. James Herman Dye, 64, is now facing two first-degree murder charges after investigators linked him to the rape and strangulation of Evelyn “Kay” Day in 1979.

Kay Day (credit: Weld County Sheriff)

The Weld County Sheriff’s Office created a Cold Case detective position in 2020, which was filled by Byron Kastilahn. Weld County Sheriff Steve Reams said the amount of cold cases he inherited was “haunting the department.” Within just months of being in the cold case detective position, Kastilahn was able to get a positive hit on DNA samples through a state database.

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Thanks to advances in technology and the WCSO’s investigation, a warrant for Dye’s arrest was issued. He was taken in to custody in Wichita, KS where he is being held at the Sedgwick County Jail awaiting extradition.

CBS4 obtained documents that painted a clearer picture of how one of Weld County’s “coldest cases on the books” was potentially solved.

Day was an employee at Aims Community College in 1979. The last time Day was seen alive was on the night of Nov. 26 of 1979. A student said she was locking the doors to a lab she worked in late at night. At home, her husband and two young children, were sleeping.

Dye was a student on the campus at the time. Law enforcement learned he was enrolled in automotive classes at the time of Day’s death.

James Dye (credit: Weld County Sheriff)

Day’s husband reported her missing the morning of November 27th, 1979. That evening two of her coworkers spotted her vehicle parked under the water tower alongside eastbound 20th St near the college. When they checked the car they found her body in the back of the station wagon. Deputies said she had been raped and strangled manually with the belt from her own jacket.

DNA swabs were taken from her vaginal area, as well as from her fingernails. At the time DNA technologies were not good enough to directly identify an attacker.

But in 2020, with a greater pool of samples and technology, WCSO was able to link Dye to the samples collected 41 years prior.

Dye has a lengthy criminal record which includes four different sexual assault arrests, two of which involved children.

Investigators said some of Dye’s peers believed he was involved in the murder as soon as the day Kay Day’s body was discovered. He allegedly came home that night with bloody clothing. He told his then-wife that someone had been killed near Aims Community College even though the story had not been featured on the news yet.

Dye was arrested once for luring a woman by asking for a ride home. He then sexually assaulted her after giving her directions which ended on a remote dirt road. Investigators suggested Dye might have done the same thing to Day.

Now in custody for the death, 41-years-later, Dye denied any responsibility in the death. He told investigators he didn’t know the victim or her case and denied having any connection.

James Dye (credit: Weld County Sheriff)

“I hate the expression justice delayed is justice denied, but that is true,” said Weld County District Attorney Michael Rourke. “We are never going to rest until we don’t have any cold cases.”

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Rourke, and Weld County Sheriff Steve Reams said the arrest of Dye was something celebrated by those who serve and protect the residents of Weld County.

“(The day Dye was linked to the case) was a day we celebrate. A lot of high fives in the office,” Reams said. “I think the suspect was very surprised (to be arrested).”

In an exclusive interview with CBS4’s Dillon Thomas, Day’s family members said they were ecstatic to see an arrest in a case they assumed would never be solved.

“We had given up, and figured it would never be solved,” said Jennifer Kerr, Day’s cousin.

Kerr, and her husband, were the only family members able to attend the press conference announcing Dye’s arrest. Day’s mother and namesake, Evelyn Kay Sr., turned 100 the same week of Dye’s arrest. Family members who were healthy enough traveled for a celebration. Kerr said she was honored to represent her family on such a monumental and awaited day.

(credit: Jennifer Kerr)

“She was a sweet quiet kind of person,” Kerr said. “This just came out of nowhere. It feels like a victory.”

“To get that phone call (saying an arrest was made), the reality of it was like wow, wow,” said James Kerr, Day’s cousin-in-law.

Jennifer recalled Day as being a light who wanted her family and friends to succeed. She said Day was a talented piano player who loved her, then, four-year-old and six-month-old sons with her whole heart.

Now able to see a photo of the man accused of the rape and murder, and to know a suspect may be held responsible, Jennifer said she had mixed emotions. She said it was saddening to know it took so long to find a suspect, yet thrilling to know accountability may be had. She said it, most of all, was confusing. When asked what she would say to the suspect if given the chance, she kept asking one thing.

“Why? Why? Why would you take the life of someone so vibrant? I can’t comprehend it,” Jennifer told Thomas.

Pending extradition Dye faces two counts of first-degree murder. One county of first-degree murder after deliberation and one count of felony first-degree murder.

The Kerr’s said they were forever grateful to the investigators who chose not to give up on a case that had grown ice cold.

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“Thank you so much for not giving up on this case. tI means so much to our family,” Jennifer Kerr said.

Dillon Thomas