The felony charges were dismissed Monday morning in Santa Clara County Superior Court.
"Despite my best efforts to convince the victim to testify, she refused. That is her legal right. Regretfully, Ray McDonald will not face a jury for what he did that night. We are disappointed that he will not be held responsible," Deputy District Attorney Chris Lamiero said in a statement.
The indictment stems from a Dec. 15, 2014 incident at the 30-year-old former professional football player's home.
The 49ers released Ray McDonald in December 2014, after San Jose police revealed the defensive lineman was under investigation for an alleged sexual assault.
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