COSTILLA COUNTY, Colo. — An undersheriff in Costilla County has been charged with assaulting an inmate in the county jail.

On Tuesday afternoon, Sheriff Danny Sanchez said Undersheriff Randy Herrera, 42, was no longer with the Costilla County Sheriff’s Office. Sanchez said Herrera resigned the day he planned to terminate him.

Herrera was charged with official oppression, assault by strangulation, knowingly or recklessly causing bodily injury and official misconduct, according to court documents. The charges were filed on Jan. 13, 2020.

The inmate Herrera is accused of assaulting was still in custody as of Tuesday, but had been transferred to a different location.

The 12th Judicial District Attorney’s Office and the CBI did their own criminal investigation.

Herrera did not have any prior complaints about using force on his record, Sanchez said.

Before coming to the Costilla County Sheriff’s Office, Herrera worked in Longmont, Thornton and Lafayette in a law enforcement capacity.

He had been with the sheriff’s office for a year, Sanchez said.

His advisement hearing is scheduled for Feb. 4.

