The office said it had fired Deputy M. DeLeon on Tuesday for being untruthful in the course of the investigation into the death of Harris County Sheriff's Deputy Darren Goforth.
In October, the Harris County Sheriff's office fired Sergeant Craig Clopton, a homicide investigator, after a receiving a report that he had sexual relations with a witness in the case.
Clopton had "consensual sexual relations" with the same woman who has claimed she had been in a sexual relationship with Goforth, court papers said.