D.C. prosecutors have dropped charges against a D.C. police officer who was accused of assaulting his girlfriend in her District home.

Calvin Willis, 52, who has been on the force for nearly 30 years, was arrested in May. At the time, authorities alleged that he slammed his 25-year-old girlfriend into a wall, pulled her hair and threatened to kill her and throw her out a window. During their argument, the woman grabbed a knife, and Willis placed his hand on his gun, according to court records.

Late Tuesday, prosecutors dropped the charges. “The U.S. attorney’s office has determined there is insufficient evidence to go forward at this time and has now dismissed the case,” spokesman William Miller said.

The case had been scheduled to go before a grand jury, but it was unclear whether it had.

Willis’s attorney, Harold D. Martin, said Willis is “very happy” that prosecutors would not pursue the case. “We’d just like this to go quietly away,” Martin said.

Still in question is Willis’s position with D.C. police. Willis, who worked in the 6th Police District, was placed on paid leave and then on unpaid leave after his arrest. Martin said an internal “administrative review” has been scheduled to determine Willis’s status with the force.

At the time of his arrest, there were questions about whether Willis would face additional charges because he had started dating his girlfriend when she was 15. The couple have two children. Miller said there was “insufficient evidence” to charge Willis with “any” crimes at this time.

At a May 9 hearing, days after his arrest, Willis’s wife and several uniformed police officers sat in the audience.

Martin said Willis, of Forestville, Md., was released from GPS monitoring Wednesday and is now allowed to return into the District. A judge had barred him from the city as a condition of his release while he awaited trial. Willis will also be able to see visit with his children, Martin said.

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