20 ILCS 2610/21

(a) The Illinois State Police shall appoint as State policemen the number of persons required for assignment to the policing of toll highways by contracts made pursuant to Section 20 of this Act; and such policemen shall have the same qualifications and shall be appointed and paid and shall receive the same benefits, as all other State policemen.

(b) The Director shall assign such policemen in accordance with the contract provisions, which may authorize temporary increases or decreases in the number of policemen so assigned when emergency conditions so require.

(c) State policemen so assigned have, in policing the toll highways, all powers and duties of enforcement and arrest which Section 16 of this Act confers upon State policemen generally in policing other public highways and other areas, and in addition have the duty to enforce all regulations established by the Illinois State Toll Highway Authority pursuant to the authority of the Toll Highway Act.