When the action is brought by any citizen on his or her own relation, as above provided, he or she shall file security for costs to be approved by the clerk, at the time the complaint is filed.
18-105.Security for costs.
Article XVIII. Quo Warranto · Not amended since adoption on record · Last verified July 20, 2026
In one sentenceRequires a citizen bringing a quo warranto action on their own relation to file security for costs, approved by the clerk, when the complaint is filed.
Full Text of 735 ILCS 5/18-105
Plain-English Summary
When a citizen relator uses the path Section 18-102 opens — suing on their own relation after the Attorney General and State's Attorney decline or fail to act — Section 18-105 attaches a condition. That citizen must file security for costs at the time the complaint is filed, and the clerk must approve it.
The requirement doesn't apply when the Attorney General or State's Attorney brings the action in their official capacity; it's tied specifically to citizen-relator suits. It gives some assurance that a citizen invoking this public remedy on their own initiative can cover the costs if the case doesn't succeed.
Frequently Asked Questions
Who must file security for costs in a quo warranto case?
A citizen bringing the action on their own relation, as Section 18-102 permits.
When must the security for costs be filed?
At the time the complaint is filed.
Who approves the security for costs?
The clerk of the court.
Does the Attorney General have to post security for costs to bring a quo warranto action?
No. Section 18-105 addresses citizen relator suits specifically, not actions brought by the Attorney General or State's Attorney in their official role.
What is the purpose of requiring security for costs from a citizen relator?
It gives assurance that costs can be covered if the citizen's quo warranto action does not succeed.
Amendment History
(Source: P.A. 82-280.)
Source & verification. Section text and amendment history are
reproduced verbatim from the Illinois Compiled Statutes, published by the
Illinois Compiled Statutes, Illinois General Assembly / Legislative Reference Bureau. Last verified July 20, 2026.
· Official source
Also known as: quo warranto security for costs illinoiscitizen relator quo warranto costsfiling quo warranto as private citizen