Cheyenne Residents Facing First-Degree Murder Charges In Death of Infant

A pair of Cheyenne residents were arrested on Wednesday in connection with the death of their four-month old infant son last summer.

According to a news release from the Cheyenne Police Department, the case started on August 8, 2025. Cheyenne Police were notified that an infant boy had been brought in by his parents, 24-year-old Joseph Hanson and 23-year-old Juliette Martinez because the child had suffered a seizure.

According to the release "Following an assessment, it was determined the baby required advanced medical care at Denver Children’s Hospital. When staff were unable to locate or contact the parents to obtain consent for the life-flight, the responding officer went to their residence to connect them with hospital personnel."

Denver Hospital Says Injuries Appeared To Be Result Of Abuse

Medical evaluations in Denver found the boy had suffered extensive injuries, including fractures and life threatening brain trauma which appeared to be the result of physical abuse.

The child was placed on life support. On September 8, the child was removed from life support and pronounced dead.

On March 20, 2026, police got an autopsy report from the Adams and Broomfield county coroner's office. The report said the manner of death was homicide.

Cheyenne Police Detectives submitted probable cause warrants to the Laramie County District Attorney's office for the arrest of Hanson and Martinez. On April 8, they were arrested without incident and booked into the Laramie County jail on charges of first degree murder and aggravated child abuse.

The release says the case is still under investigation.