A formal announcement by District Attorney Kenneth Thompson is expected to be made Wednesday. It was unclear Tuesday afternoon if charges would include manslaughter.
Liang, who reportedly texted his union representative before calling for an ambulance after shooting Gurley in the chest on November 20, said he had fired his gun accidentally while patrolling the Louis H. Pink Houses in East New York.
Following the shooting, police commissioner Bill Bratton called Gurley a "total innocent."
Gurley's death became one of the focal points of the Black Lives Matter movement, which called attention to institutional racism and police brutality after the police killings of Michael Brown in Ferguson, Missouri and Eric Garner in Staten Island last year. Neither officer in those cases was indicted.