Even though a grand jury has ruled that the March 13 fatal shooting of Breonna Taylor by Louisville Metro Police officers was justified as self-defense, a federal investigation into the incident continues.

The FBI opened its investigation into Taylor's fatal shooting in May, saying it would "collect all available facts and evidence and will ensure that the investigation is conducted in a fair, thorough and impartial manner."

"FBI Louisville continues its federal investigation into all aspects of the death of Breonna Taylor," spokesman Tim Beam said in an email to the Courier-Journal . "This work will continue beyond the state charges announced today." 

Three officers were involved in the shooting: Sgt. Jonathan Mattingly, Det. Myles Cosgrove, and former Det. Brett Hankison. Mattingly was shot in the thigh during the incident by Taylor's boyfriend Kenneth Walker and he and the other officers returned fire, Kentucky Attorney General Daniel Cameron says. Taylor was killed. Walker was not hit.

Hankison is the only officer who was charged Wednesday by state officials. He was charged with three counts of wanton endangerment because three of the shots he fired into Taylor's apartment went into other occupied apartments. He faces up to five years per count.

Because the Fourth Amendment of the U.S. Constitution guarantees the right against unreasonable searches or seizures, the warrant process in the Taylor case could be part of the FBI review.