Thornton police on Friday announced the department has concluded its investigation into a March homicide case that ended with the suspect’s suicide.

Thornton Police Department officers on March 15 responded to a home in the 13200 block of Downing Street after Chad Gililland, 42, called 911 to report his wife Cheyenne Gililland, 43, was unresponsive. When officers arrived, Cheyenne was found with no visible sign of fatal injuries and was pronounced dead at the scene, according to a TPD news release.

After extensive forensic testing by the Adams County Coroner’s office, the coroner determined on Wednesday that the manner of death was homicide due to closed head injuries caused by blunt force trauma, according to the release. Authorities believe the injuries were sustained during a physical assault.

Thornton police detectives, along with the 17th Judicial District Attorney’s office, established probable cause and believe Chad Gililland was responsible for his wife’s death, police said. However, Gililland died by suicide on March 23, police said, meaning the case is now considered closed.

“No family should have to experience a loss like this,” Thornton Police Chief Jim Baird said in the release. “Our thoughts remain with Cheyenne’s loved ones and everyone affected by this tragedy. We hope that sharing information about this case brings attention to the seriousness of domestic violence and reminds anyone struggling that they are not alone and support is available.”  

Editor’s note: This story includes the issue of suicide. For resources to help, call the Colorado Mental Health line at 988 or visit www.988colorado.com.