Martin Herrmann is charged with improper photography or visual recording.
According Tarrant County search warrant affidavits, Herrmann, 50, put pens in several locations his 24-year-old stepdaughter's bathroom and bedroom at the home both were living in in Fort Worth.
Fort Worth Police also say that Herrmann installed a motion detector in the woman's bedroom for "security" purposes.
The woman -- who has a young child -- was originally concerned that the pens were in within reach of her child, but she became more suspicious when she noticed more pens outside of the child's reach.
The woman eventually looked at the pens and realized they were actually hidden cameras that showed her in her bedroom and bathroom.
Hermann was arrested in December, but The Fort Worth Star-Telegram reports that he posted $25,000 bail.
If convicted, Hermann faces up to 2 years in prison and up to a $10,000 fine.
Herrmann was an Arlington-based T.A.B.C. agent before his arrest, but he was fired from the agency after he didn't cooperate into their independent investigation into the incident.
Herrmann previously worked for the T.A.B.C. in the Midland-Odessa area.