The laws of the game are governed and instituted by the international body FIFA. For a comprehensive look at the laws of football, visit the FIFA website indicated by the URL below.

FIFA - Laws of the Game

RULINGS:

LAW 4: Quote in part "Each goal keeper wears colours that distinguish him/her from the other players, the Referee and the Assistant Referees."

Goal keepers are NOT permitted to wear black tops that may cause confusion with the referee uniform. It is permitted to have some black on the top however such as a stripe or panel area as long as it is not predominately black, and as long as there is no risk of confusion.

Black tops for player uniforms are NOT permitted for the same reason.