RulesofCivilProcedure.com Civil Procedure · Every State

Rule 224.Discovery Before Suit to Identify Responsible Persons and Entities

Article II. Rules on Civil Proceedings in the Trial Court · Part E. Discovery, Requests for Admission, and Pretrial Procedure · Last amended 2018 · Last verified July 20, 2026

In one sentenceRule 224 lets someone who's been hurt but doesn't know who's responsible file a targeted, time-limited discovery action to find out before suing.

Full Text of Ill. S. Ct. R. 224

Text sizeJump to: (a) (b) (c)

(a) Procedure.
(1) Petition.
(i) A person or entity who wishes to engage in discovery for the sole purpose of ascertaining the identity of one who may be responsible in damages may file an independent action for such discovery.
(ii) The action for discovery shall be initiated by the filing of a verified petition in the circuit court of the county in which the action or proceeding might be brought or in which one or more of the persons or entities from whom discovery is sought resides. The petition shall be brought in the name of the petitioner and shall name as respondents the persons or entities from whom discovery is sought and shall set forth: (A) the reason the proposed discovery is necessary and (B) the nature of the discovery sought and shall ask for an order authorizing the petitioner to obtain such discovery. The order allowing the petition will limit discovery to the identification of responsible persons and entities and where a deposition is sought will specify the name and address of each person to be examined, if known, or, if unknown, information sufficient to identify each person and the time and place of the deposition.
(2) Summons and Service. The petitioner shall serve upon the respondent or respondents a copy of the petition together with a summons that is prepared by utilizing, or substantially adopting the appearance and content of, the form provided in the Article II Forms Appendix.
(b) Expiration and Sanctions. Unless extended for good cause, the order automatically expires 60 days after issuance. The sanctions available under Supreme Court Rule 219 may be utilized by a party initiating an action for discovery under this rule or by a respondent who is the subject of discovery under this rule.
(c) Expenses of Complying. The reasonable expenses of complying with the requirements of the Order of Discovery shall be borne by the person or entity seeking the discovery.

Plain-English Summary

Someone who wants discovery for the sole purpose of identifying a potential defendant can file an independent verified petition, naming as respondents the people or entities likely to have that information, and explaining why the discovery is needed and what form it should take. The court's order stays narrow, limited to identifying responsible parties, and spells out who gets deposed and when if a deposition is involved.

The petitioner serves the respondents with the petition and a summons modeled on the form in the rules' forms appendix. Once granted, the discovery order automatically expires 60 days after issuance unless extended for good cause — this tool is meant to answer one question, not open a general investigation.

Rule 219 sanctions apply to both sides if the process is abused, and the person seeking the discovery bears the reasonable cost of getting it.

Frequently Asked Questions

What is Rule 224 discovery used for?
To identify a person or entity who may be responsible in damages, before a lawsuit is filed against them.
How does someone start a Rule 224 action?
By filing a verified petition explaining why the discovery is needed and what form it should take, naming the likely sources of that information as respondents.
How long does a Rule 224 discovery order last?
It automatically expires 60 days after issuance unless extended for good cause.
Who pays for complying with a Rule 224 discovery order?
The person or entity seeking the discovery bears the reasonable expense of compliance.
Can Rule 224 be used to get more than the identity of a responsible party?
No, the order is limited to identifying responsible persons and entities, not a broader investigation into the merits.

Committee Comments

(August 1, 1989)

New Rule 224 was adopted effective August 1, 1989. This rule provides a tool by which a person or entity may, with leave of court, compel limited discovery before filing a lawsuit in an effort to determine the identity of one who may be liable in damages. The rule is not intended to modify in any way any other rights secured or responsibilities imposed by law. It provides a mechanism for plaintiffs to ascertain the identity of potential defendants in a variety of civil cases, including Structural Work Act, products liability, malpractice and negligence claims. The rule will be of particular benefit in industrial accident cases where the parties responsible may be known to the plaintiff’s employer, which may immunize itself from suit. The rule facilitates the identification of potential defendants through discovery depositions or through any of the other discovery tools set forth in Rules 201 through 214. The order allowing the petition will limit discovery to the identification of responsible persons and entities. Therefore, Supreme Court Rule 215, dealing with mental and physical exams, and Supreme Court Rule 216, dealing with requests to admit, are not included as means of discovery under this rule.

Amendment History

Adopted June 19, 1989, effective August 1, 1989; amended May 30, 2008, effective immediately; amended Dec. 29, 2017, eff. Jan. 1, 2018.

Source & verification. Rule text, official Committee Comments, and amendment history are reproduced verbatim from the Illinois Supreme Court Rules, promulgated by the Supreme Court of Illinois. Last verified July 20, 2026. · Official source
Also known as: pre-suit discoveryidentify responsible partyJohn Doe discovery Illinoisdiscovery before lawsuit filed