705 ILCS 96/10-15

(a) A person duly and in good faith attending a State court proceeding in which the person is a party, a witness, a potential witness, or a court companion of a party, witness, or potential witness is privileged from civil arrest while going to, remaining at, and returning from the court proceeding, including: (1) at the place of the court proceedings; (2) within the courthouse building; (3) on the premises of the courthouse, including parking facilities serving the courthouse; (4) on any sidewalk, parkway, and street surrounding the courthouse and its premises; and (5) on any public way within 1,000 feet of the courthouse including a sidewalk, parkway, or street. (b) Nothing in this Section shall be construed to narrow, or in any way lessen, any common law or other right or privilege of a person privileged from arrest under this Act or otherwise. (c) The protections in this Section apply regardless of whether a judicial order under Section 10-20 is issued or a court otherwise implements this Act by a rule or order. (d) Nothing in this Section precludes the execution of a criminal arrest warrant issued by a judge or a criminal arrest based on probable cause for a violation of criminal law.