'Meet the Press' Got the Green Light for Magazine Demo with David Gregory

An official from the D.C. police told a member of the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives that David Gregory COULD display a high capacity magazine on "Meet the Press" Sunday ... TMZ has learned.

Well-placed law enforcement sources tell TMZ ... a staffer from "Meet the Press" called ATF before the show aired to inquire about the legality of David holding the empty magazine during a segment on gun control. We're told the ATF person contacted the D.C. police to find out if the District of Columbia -- the place where the show is broadcast -- had a law prohibiting such a display.

Our sources say the D.C. police official informed ATF David could legally show the magazine, provided it was empty. An ATF official then called the staffer from "Meet the Press" to inform them they could use the magazine.

D.C. police released a statement today, saying "NBC contacted the Metropolitan Police Dept. inquiring if they could utilize a high capacity magazine for this segment. NBC was informed that possession of a high capacity magazine is not permissible and the request was denied."

It appears "Meet the Press" may have gotten 2 different answers from law enforcement.