John Marshall Hibbert


Staff at the Frederick County Adult Detention Center found a 39-year-old inmate dead in his cell early Monday, the sheriff’s office announced in a press release Tuesday.

The Frederick County Sheriff’s Office is investigating the death of John Marshall Hibbert, of Knoxville, who was found dead at 5:22 a.m. Monday during breakfast wake-up.

Hibbert was found unresponsive in his bunk, on his back, according to the press release. The release said evidence suggests that Hibbert died by suicide. Investigators found a strip of a T-shirt that may have been used in the suicide, the release said. That material was not visible during previous cell checks.

Electronic security logs confirmed overnight cell checks were made as required by staff, according to the release. Correctional officers administered CPR, which was unsuccessful.

Hibbert was arrested in July and was awaiting trial on charges of child pornography possession, child pornography distribution, and sexual abuse of a minor. At the time of his arrest, Hibbert was employed by Frederick County Public Schools but served as a non-school-based employee.

Hibbert’s body has been taken to the Office of the Chief Medical Examiner in Baltimore for an autopsy.