Ill. Admin. Code tit. 95, § 400.610
a) Privilege Concerning Compulsory Self-Incrimination
2) Standing
3) Exercise of the Privilege. If a witness states that the answer to a question may tend to incriminate him or her, the witness may not be required to answer unless facts and circumstances are such that no answer the witness might make to the question could have the effect of tending to incriminate the witness or that the witness has, with respect to the question, waived the privilege against self-incrimination. A witness may not assert the privilege if the witness is not subject to criminal penalty as a result of an answer by reason of immunity, running of the statute of limitations, or similar reason.
6) Effect of Claiming the Privilege
b) Waiver of the Privilege Against Self-Incrimination
2) Counsel
B) If an accused or suspect interrogated requests counsel, any subsequent waiver of the right to counsel obtained during custodial interrogation concerning the same or different offenses is invalid unless the prosecution can demonstrate by a preponderance of the evidence that: