The Air Force Court of Criminal Appeals has overturned the rape convictions of a former master sergeant at Joint Base San Antonio-Lackland.

Former Master Sgt. Michael Silva was convicted in January 2015 of raping a basic trainee in 1995 on two occasions, and raping another senior airman who was his ex-wife in 2007. He was sentenced to 20 years confinement, a dishonorable discharge, forfeiture of all pay and allowances, and a reduction to E-1.

The appeals court ruled July 19 that the military judge “committed prejudicial error in her instructions to the court members” during the court-martial. Specifically, the judge improperly told the court members that if they decided one of the alleged sexual assaults occurred, they could use that as evidence that the defendant had a propensity to commit sexual assault when considering the other alleged offenses.

That may have been a proper reading of the law at the time. However, in a subsequent, unrelated Army case — United States vs. Hills — the U.S. Court of Appeals for the Armed Forces ruled in June 2016 that charged offenses may not be used as evidence of a defendant’s propensity to commit other charged offenses, and that the standard instruction given to panel members regarding such propensity evidence unconstitutionally undermined the presumption of innocence.

Even though the Hills case was decided in June 2016, after Silva’s conviction, the appeals court said it still applied during his appeal process.

The Air Force began investigating Silva for sexual assault as part of a wide-ranging investigation into sexual assault at Lackland. That investigation began after a recruit reported the rape of a fellow trainee by an MTI, who was not Silva, in 2011. Eventually, the Lackland scandal led to the convictions of dozens of former instructors who were accused of offenses ranging from unprofessional relationships to rape.

The former basic trainee who accused Silva of sexual assault testified that he woke her in her dorm room one night shortly after she arrived at basic training, led her to her car, forced her to perform oral sex, and then raped her. The former trainee testified Silva told her that if she reported what happened, “no one would believe her and it would ruin her career,” the decision said.

A few days later, the former trainee said, Silva again came to her dorm at night, told her to get in his car, and demanded she put her head down “so that she could not see where they were going.”

Silva “then ... made a comment that she interpreted as a threat to kill her if she did not do as he said,” according to the Air Force appeals court decision. After driving for less than 20 minutes, the former trainee testified, Silva stopped and led her into a darkened building, where she said he raped her repeatedly and choked her. She was medically discharged in late 1995 without completing basic military training, according to the appeals court decision.

Silva’s ex-wife also testified that he raped her in 2007 after their divorce had been initiated. She reported the alleged rape shortly afterward to her first sergeant, which led the Office of Special Investigations to open up an investigation. However, she later wrote a contradictory statement for OSI in which she said she didn’t believe Silva raped her, which led to that investigation being dropped.

While OSI was investigating the basic trainee’s allegations, investigators re-interviewed Silva’s ex-wife and her allegations were included in his court-martial.

Silva was found not guilty of another charge of raping his first ex-wife several times between 1992 and 1993.

In the decision, the appeals court disagreed with prosecutor’s arguments that the evidence of Silva’s guilt was “overwhelming,” and cited several weaknesses in the case, including that: the alleged crimes occurred so long in the past; there were no eyewitnesses, other than the victims; there was no physical, scientific, or photographic evidence; and the only woman who reported the alleged crimes to law enforcement before 2012 recanted her initial allegation.