Breonna Taylor wasn’t charged in court and persecuted (technically it was her bf who was shooting back). Irrespective of whether her death was legal or not, The question was simply about the legality. Kenneth Walker, boyfriend of Breonna Taylor, was never prosecuted.
Yes, the charges were eventually dropped, but Walker spent a couple of months in jail. Taylor's killing was an extrajudicial execution, as her murderers weren't charged. Walker can't sue the cops, thanks to qualified immunity, but the cop he shot is suing him.