A year and a half ago, a former student-athlete named Michael L. Johnson was found guilty of, among other crimes, infecting a sexual partner with HIV.

Also known by the nickname Tiger Mandingo, Johnson was a wrestler at Lindenwood University, near St. Louis, from 2012 until his arrest in 2013. Before Tuesday, Johnson, now in his mid-20s, had been serving the beginning of a 30-year sentence.

But a panel of appeals court judges recently reversed the trial court’s judgment. The prosecution rendered Johnson’s trial fundamentally unfair, the panel wrote in an opinion Tuesday, by using cellphone recordings that “were not disclosed to the defense until the morning of the first day of the trial.”

The wrestler discovered he was HIV positive in early January 2013, after a medical exam at Lindenwood University. A few weeks later, Johnson had unprotected sex with a fellow student, known only by the initials D.K.-L. in court documents. The student would testify in court that Johnson did not disclose his HIV-positive status.

A month after Johnson’s positive HIV test, physicians diagnosed D.K.-L., too, with HIV. The doctors determined that the student only recently acquired the HIV infection. Johnson was the sole person, D.K.-L. testified, with whom he had had sex in the previous year. When D.K.-L. saw that Johnson continued to use hookup apps without informing potential partners he had HIV, the student contacted the Saint Charles police. They arrested Johnson on Oct. 10, 2013.

During the trial, Johnson remained adamant that he informed his partners of the positive HIV test. He pleaded not guilty. The prosecution, however, impeached his testimony using three clips of cellphone conversations, recorded while Johnson was jailed. In one snippet of phone conversation, Johnson admitted he was just “pretty sure” he had informed his partners he was HIV positive.

After slightly more than two hours of deliberation, a jury declared Johnson guilty of three crimes, all felonies under Missouri law: one count of recklessly infecting a sexual partner with HIV, one count of recklessly exposing a partner to HIV and three counts of attempting to recklessly infect a partner with HIV. In July 2015, Judge Jon A. Cunningham of the Circuit Court for St. Charles County sentenced Johnson to 30 years in prison.

The outcome was condemned by human rights and LGBT advocates as based on outdated policy. The Missouri criminal law that Johnson had violated dated to the late 1980s, a holdover from a time before antiretroviral therapies and pre-exposure prevention drugs, the critics argued.

“The social stigma of being black, gay and HIV-positive was furthered in a courtroom where Judge Cunningham adjudicates through the frame of 1987 laws that respond largely to public panic rather than grounded science,” wrote Jeffrey Q. McCune, a Washington University gender and African American studies professor, in an op-ed in the Saint Louis Post-Dispatch after Johnson’s sentencing.

Tim Lohmar, a prosecutor for St. Charles County in Missouri, disputed that the charges involved Johnson’s sexual orientation or race. In an August 2015 opinion piece also published at the Post-Dispatch, Lohmar wrote, “It was about the fact that Johnson intentionally withheld his medical status from multiple sex partners, and in doing so, denied them the right to make an informed decision as to whether or not they should engage in sexual activity with someone who has the potential to expose them to HIV.”

“The sex itself was not the crime. Consensual sex among adult individuals, regardless of one’s sexual orientation or one’s status as a carrier of a communicable disease, is not a crime,” the prosecutor added. “What is a crime is when one partner fails to disclose his HIV status to a sexual partner.”

Presiding Missouri Court of Appeals’ Eastern District Judge James M. Dowd wrote Tuesday that Johnson’s trial was rendered “fundamentally unfair” by the prosecutors; they tarried too long handing over the cellphone calls recorded while Johnson was in the county jail. “The State’s blatant discovery violation here is inexcusable,” the judges concluded.

Scott Schoettes, a lawyer with the LGBT rights organization Lambda Legal who said he assisted Johnson’s public defender, said the group was elated by the reversal. “Living with HIV is not a crime,” Schoettes said in a statement. “Except in the most extreme cases, the criminal law is far too blunt an instrument to address the subtle dynamics of HIV disclosure.”

Johnson’s attorney also celebrated the decision. “Statutes like the one used to prosecute Mr. Johnson are inherently problematic, as they promote stigma and animus towards people living with HIV in violation of their legal and constitutional rights,” Lawrence Lustberg, Johnson’s lawyer, said in a statement to the AP.

To his friends and fellow wrestlers, Johnson was sometimes known by his nickname, Tiger. In high school, as Johnson said in a 2014 profile at BuzzFeed News, a friend added Mandingo. Johnson embraced it, using it as an online handle for his dating and social networking sites. He took Mandingo to be the title of a “brave black slave fighter.” (He also told BuzzFeed he was aware of its slang association for a well-endowed black man.)

“I know what it means to me — a black slave that’s a fighter,” he said in 2014. “I consider myself a fighter.”

Johnson’s legal fight will continue: The panel of judges overturned Johnson’s conviction and remanded the case for a new trial.

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