515 ILCS 5/1-185
Authorized employees of the Department are empowered, under law, to enter all lands and waters to enforce this Code. Authorized employees are further empowered to examine all buildings, private or public clubs (except dwellings), fish markets, cold storage houses, locker plants, camps, vessels, cars (except sealed railroad cars or other common carriers), conveyances, vehicles, water craft, or any other means of transportation or shipping, tents, game bags, game coats, or other receptacles and to open and examine any box, barrel, package, or other receptacle in the possession of a common carrier, that they have reason to believe contains aquatic life or any part of aquatic life taken, bought, sold or bartered, shipped, or had in possession contrary to this Code, including administrative rules, or that the receptacle containing the aquatic life is falsely labeled.
Authorized employees of the Department shall be given free access to and shall not be hindered or interfered with in making an entry and examination. Any license held by a person preventing free access or interfering with or hindering an employee shall not be issued to that person for the period of one year after his or her action.
Employees of the Department as specifically authorized by the Director are empowered to enter all lands and waters for purposes of pollution investigations, State and federal permit inspections, as well as aquatic life and wildlife censuses or inventories, and are further empowered to conduct examination of equipment and devices in the field, under law, to ensure compliance with this Code.
515 ILCS 5/1-185