RIVERSIDE (CBS) — A Beaumont police officer accused of firing a pepper spray gun so close to a woman’s face that it permanently blinded her pleaded not guilty Thursday to assault resulting in great bodily injury and other felonies.

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Enoch Clark, 36, could face more than 20 years in prison if convicted of the disabling assault on Monique Hernandez on Feb. 21.

A Riverside grand jury last week indicted Clark on the assault with great bodily injury charge, as well as one count each of assault by a peace officer, assault with a non-lethal weapon, unnecessary force causing injury and allegations of using a weapon during a felony and producing great bodily injury in the course of a crime.

The policeman, who is on paid administrative leave from his job, remains free on $50,000 bail.

According to the D.A.’s office, sheriff’s detectives determined that Clark had fired a JPX pepper spray pistol — which resembles a Star Trek Phaser and ejects propellant at 400 mph — ten inches from Hernandez’s face in the process of trying to arrest her, damaging both of her eyes. The recommended range to fire a JPX device is six to 16 feet from a target.

Prosecutors said the police officer had been trained in the proper use of the pistol.

Clark’s attorney could immediately be reached for comment.

Los Angeles-based civil attorney Milton Grimes, who is representing Hernandez, is planning to file a lawsuit on behalf of Hernandez and her parents against Clark and the police department alleging excessive use of force and negligent infliction of mental and physical distress.

On the day of the alleged assault, Hernandez had driven her younger sister to pick up the woman’s 2-year-old daughter, who was visiting her biological father, according to Grimes.

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He said during the ensuing child custody exchange, Hernandez’s sister and ex-boyfriend got into an argument, resulting in the latter grabbing the woman, at which point Hernandez intervened, grappling with the man to protect her sister.

The man’s mother called police, and Hernandez left the location with her sister and the 2-year-old, Grimes said.

According to the attorney, when Hernandez arrived at her parents’ house a few minutes later, Officer Clark was waiting to question her about what had happened during the child custody exchange. Grimes said Hernandez’s parents and several siblings observed the encounter, and at no time was the victim aggressive.

“For whatever reason, this officer decides to give her a field sobriety test,” Grimes said. “Then he tries to give her a breathalizer test, but the unit is not working right, so finally he decides to arrest her for being under the influence.

“She asks him, `What did I blow?’ And he tells her to shut up and slams her head to the hood of the car. He got her hands behind her back. She’s not biting or resisting. But he puts this pepper spray weapon to her head and pulls the trigger. She hears a boom, and that’s the last thing she remembers.”

According to Grimes, paramedics responded and washed the propellant from Hernandez’s face, then left. He said Clark and a backup officer transported the woman to a nearby hospital, handcuffed her to a bed for 45 minutes and then removed the shackles and told her she was free to go.

Grimes said the victim’s parents took her to a hospital in Redlands, where she stayed for a week and “came out totally blind.”

“Her right cornea is split and the nerve in her left eye is irreparably damaged,” Grimes said. “She says she can make out light.”

Clark will return to court on May 29.

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