Brett Hankison, sacked by police in June, appeared free in a brief telephone hearing.
The ex-police officer charged after the death of Breonna Taylor, a young African-American girl killed during a search in March in Louisville, Kentucky, pleaded not guilty on Monday to the three counts against him.
None of the three police officers who fired during the operation has been charged with the death of the young woman.
Brett Hankison is being prosecuted for endangering the lives of others, his shots having crossed the apartment of neighbors of Breonna Taylor.
"Threats against him on social networks"
No charges were brought against the other two police officers.
A jury ruled that they had acted in self-defense.
His lawyer, Stewart Matthews, has demanded that he be allowed to keep the weapons he owns "for self-defense" because of "threats against him on social media."
His request was rejected by the presiding judge.
His indictment last week sparked angry protests in Louisville and across the country, with protesters denouncing legal treatment they said was too lenient towards the three officers.
A hearing October 28
The next hearing has been set for October 28.
He faces up to fifteen years in prison.
Breonna Taylor, a 26-year-old nurse, was killed in the middle of the night at her home on March 13 when the three police officers arrived there with a so-called "no knock" arrest warrant, which allows them to enter. at a suspect without announcing himself.
When they arrived, his companion had opened fire with a legally owned weapon, believing he was dealing with burglars.
The agents, who claim to have identified themselves before entering, retaliated and Breonna Taylor had received several bullets.
His death has returned to center stage as part of the major anti-racist protests that have crossed the United States since the death of George Floyd, a black forty-something suffocated by a white policeman in Minneapolis at the end of May.
