620 ILCS 15/7

It shall be unlawful for any person who has been denied or forbidden to move any aircraft upon the ground or surface of a public airport or to take off from or land, except in a declared emergency, at a public airport under the provisions of this Act, and any person acting under the direction of such person, to move any aircraft or take off from or land, except in a declared emergency, at such public airport except as authorized or required by the individual charged with the responsibility of grounding aircraft.