During a court hearing for Engman's case last week, Schlueter showed a video of a police tactics consultant shocking Engman for a few seconds, in order to demonstrate that Engman's injuries were more severe than those caused in the video. Schlueter and his brother were also shocked in the video, Schlueter said.

But, after the tape was shown, San Bernardino County Deputy District Attorney Dan Ross said that Schlueter and his consultant Roger Clark may have violated the state's human experimentation law, which requires patients to sign waivers for medical experiments, according to Schlueter and local news reports.

When questioned by Ross, Clark testified that he was not certified to use the Taser and that he had not obtained waivers from Engman, Schlueter or his brother.

"It's something we're going to look at," Ross said of filing criminal charges, according to the Inland Valley Daily Bulletin. He declined to comment when contacted by ABC News.

Judge Katrina West postponed the hearing, advised Clark of his right against self-incrimination and appointed an attorney to represent him. She also advised Schlueter of his rights.

Schlueter said the move by prosecutors was an attempt to stop him from showing how police used excessive force on Engman. He said he had to shock Engman because he could not get studies on injuries caused by the weapons from Taser International. "I've never, ever heard of a single case like this," Schlueter said.

Ross told the Daily Bulletin that Clark's experiment damaged his credibility as an expert.

Neil Shouse, a former Los Angeles prosecutor, said the case was "very unusual. & This is first time I've heard of something like this," he said.

The state's human experimentation laws require that subjects of medical experiments be given an explanation of the purposes and risks of any experiment. They must give their written consent to participate. Violations can carry penalties of up to one year in jail or a $50,000 fine.

Alexander Capron, a professor of law and medicine at the University of Southern California, and an expert in medical ethics, said the law, which applies to "medical experiments," was intended to apply to medical research.

Told about Schlueter's case, Capron said, "This doesn't sound like research, as that's usually understood."

"If he's allowing himself to be stunned for the purpose of producing evidence in court, the notion that they're engaged in research seems laughable on its face," he said.