From the New York Times:
The shooting on Saturday night immediately raised questions about the police’s use of deadly force, especially in a crowded area where bystanders were in the line of fire. On Sunday, police officials, including the commissioner, Raymond W. Kelly, refused to say if the shooting appeared justified, saying that the circumstances were being investigated.
Department guidelines say officers may not fire their weapons unless they believe they or other people are in imminent danger of death or serious injury, or if doing so will “unnecessarily endanger innocent persons.” Nonetheless, the courts and the Police Department generally give officers great leeway in deciding when to fire their weapons….
The two officers were placed on administrative duty pending the department’s internal investigation, as officers typically are after a shooting. The review process can result in retraining for the officer or more serious disciplinary action, including the rarely employed option of dismissal from the force. (That occurred for one officer after the 2006 killing of Sean Bell, who was unarmed. Three others were forced to resign; one was exonerated in a departmental hearing.)