Former U.S. Olympic equestrian Darren Chiacchia has pleaded not guilty to violating a Florida law requiring HIV-positive people to disclose their status before having sex with a partner, reports.

According to the article, Chiacchia—a 2004 bronze medalist—was arrested last month and charged with a first degree felony after an unnamed male sexual partner came forward and claimed that Chiacchia told him at the beginning of their relationship that he did not have any sexually transmitted infections. The pair had unprotected sex several times between February and June 2009.

The article does not mention whether Chiacchia’s former partner is positive.

The partner told investigators that he learned of Chiacchia’s HIV status after coming across medical documents during a trip to New York. He also showed investigators an e-mail he received, which he said supports the claim that Chiacchia was fully aware of his HIV status in 2008.