(1) DISCOVERY METHODS. Parties may obtain discovery by one or more of the following methods: depositions upon oral examination or written questions; written interrogatories; production of documents or things or permission to enter upon land or other property, for inspection and other purposes; physical and mental examinations; and requests for admission. Unless the court orders otherwise under sub. (3), and except as provided in ss. 804.015, 804.045, 804.08 (1) (am), and 804.09, the frequency of use of these methods is not limited.
804.01.General provisions governing discovery.
Ch. 804: Depositions and Discovery · Last amended 2017 · Last verified July 15, 2026
In one sentenceSection 804.01 lays out the general ground rules for Wisconsin civil discovery -- the discovery methods available, the proportional relevance standard that bounds them, protections for trial-preparation materials and expert opinions, protective orders, sequencing, the duty to supplement, custody of discovery documents, and how to claw back inadvertently produced privileged material.
Full Text of Section 804.01
(2) SCOPE OF DISCOVERY. Unless otherwise limited by order of the court in accordance with the provisions of this chapter, the scope of discovery is as follows:
(a) In general. Parties may obtain discovery regarding any nonprivileged matter that is relevant to any party’s claim or defense and proportional to the needs of the case, considering the importance of the issues at stake in the action, the amount in controversy, the parties’ relative access to relevant information, the parties’ resources, the importance of the discovery in resolving the issues, and whether the burden or expense of the proposed discovery outweighs its likely benefit. Information within this scope of discovery need not be admissible in evidence to be discoverable. (am) Limitations. Upon the motion of any party, the court shall limit the frequency or extent of discovery if it determines that one of the following applies: 1. The discovery sought is cumulative or duplicative, or can be obtained from some other source that is more convenient, less burdensome, or less expensive. 2. The burden or expense of the proposed discovery outweighs its likely benefit or is not proportional to the claims and defenses at issue considering the needs of the case, the amount in controversy, the parties’ resources, the complexity and importance of the issues at stake in the action, and the importance of discovery in resolving the issues.
(b) Insurance agreements. A party may obtain discovery of the existence and contents of any insurance agreement under which any person carrying on an insurance business may be liable to satisfy part or all of a judgment which may be entered in the action or to indemnify or reimburse for payments made to satisfy the judgment. Information concerning the insurance agreement is not by reason of disclosure admissible in evidence at trial. (bg) Third party agreements. Except as otherwise stipulated or ordered by the court, a party shall, without awaiting a discovery request, provide to the other parties any agreement under which any person, other than an attorney permitted to charge a contingent fee representing a party, has a right to receive compensation that is contingent on and sourced from any proceeds of the civil action, by settlement, judgment, or otherwise.
(c) Trial preparation: materials. 1. Subject to par. (d) a party may obtain discovery of documents and tangible things otherwise discoverable under par. (a) and prepared in anticipation of litigation or for trial by or for another party or by or for that other party’s representative (including an attorney, consultant, surety, indemnitor, insurer, or agent) only upon a showing that the party seeking discovery has substantial need of the materials in the preparation of the case and that the party seeking discovery is unable without undue hardship to obtain the substantial equivalent of the materials by other means. In ordering discovery of such materials when the required showing has been made, the court shall protect against disclosure of the mental impressions, conclusions, opinions, or legal theories of an attorney or other representative of a party concerning the litigation. This protection is forfeited as to any material disclosed inadvertently in circumstances in which, if the material were a lawyer-client communication, the disclosure would constitute a forfeiture under s. 905.03 (5). This protection is waived as to any material disclosed by the party or the party’s representative if the disclosure is not inadvertent. 2. A party may obtain without the required showing a statement concerning the action or its subject matter previously made by that party. Upon request, a person not a party may obtain without the required showing a statement concerning the action or its subject matter previously made by that person. If the request is refused, the person may move for a court order. Section 804.12 (1) (c) applies to the award of expenses incurred in relation to the motion. For purposes of this paragraph, a statement previously made is a written statement signed or otherwise adopted or approved by the person making it, or a stenographic, mechanical, electrical, or other recording, or a transcription thereof, which is a substantially verbatim recital of an oral statement by the person making it and contemporaneously recorded.
(d) Trial preparation: experts. Discovery of facts known and opinions held by experts, otherwise discoverable under par. (a) and acquired or developed in anticipation of litigation or for trial, may be obtained as follows: 1. A party may through written interrogatories require any other party to identify each person whom the other party expects to call as an expert witness at trial. A party may depose any person who has been identified as an expert whose opinions may be presented at trial. Upon motion, the court may order further discovery by other means, subject to such restrictions as to scope and such provisions, pursuant to subd. 3. concerning fees and expenses as the court considers appropriate. 2. A party may, through written interrogatories or by deposition, discover facts known or opinions held by an expert who has been retained or specially employed by another party in anticipation of litigation or preparation for trial and who is not expected to be called as a witness at trial only upon motion showing that exceptional circumstances exist under which it is impracticable for the party seeking discovery to obtain facts or opinions on the same subject by other means. 3. Unless manifest injustice would result, the court shall re- quire that the party seeking discovery pay the expert a reasonable fee for the time spent in responding to discovery under the last sentence of subds. 1. and 2.; and with respect to discovery obtained under the last sentence of subd. 1., the court may require, and with respect to discovery obtained under subd. 2., the court shall require, the party seeking discovery to pay the other party a fair portion of the fees and expenses reasonably incurred by the latter party in obtaining facts and opinions from the expert.
(e) Specific limitations on discovery of electronically stored information. 1g. A party is not required to provide discovery of any of the following categories of electronically stored information absent a showing by the moving party of substantial need and good cause, subject to a proportionality assessment under par. (am) 2.: a. Data that cannot be retrieved without substantial additional programming or without transforming it into another form before search and retrieval can be achieved. b. Backup data that are substantially duplicative of data that are more accessible elsewhere. c. Legacy data remaining from obsolete systems that are unintelligible on successor systems. d. Any other data that are not available to the producing party in the ordinary course of business and that the party identifies as not reasonably accessible because of undue burden or cost. In response to a motion to compel discovery or for a protective order, the party from whom discovery is sought is required to show that the information is not reasonably accessible because of undue burden or cost. If that showing is made, the court may order discovery from such sources only if the requesting party shows good cause, considering the limitations of par. (am). The court may specify conditions for the discovery. 1r. No party may serve a request to produce or inspect under s. 804.09 seeking the discovery of electronically stored information, or respond to an interrogatory under s. 804.08 (3) by producing electronically stored information, until after the parties confer regarding all of the following, unless excused by the court: a. The subjects on which discovery of electronically stored information may be needed, when such discovery should be completed, and whether discovery of electronically stored information shall be conducted in phases or be limited to particular issues. b. Preservation of electronically stored information pending discovery. c. The form or forms in which electronically stored information shall be produced. d. The method for asserting or preserving claims of privilege or of protection of trial-preparation materials, and to what extent, if any, the claims may be asserted after production of electronically stored information. e. The cost of proposed discovery of electronically stored information and the extent to which such discovery shall be limited, if at all, under sub. (3) (a). f. In cases involving protracted actions, complex issues, or multiple parties, the utility of the appointment by the court of a referee under s. 805.06 or an expert witness under s. 907.06 to supervise or inform the court on any aspect of the discovery of electronically stored information. 2. If a party fails or refuses to confer as required by subd. 1r., any party may move the court for relief under s. 804.12 (1). 3. If after conferring as required by subd. 1r., any party objects to any proposed request for discovery of electronically stored information or objects to any response under s. 804.08 (3) proposing the production of electronically stored information, the objecting party may move the court for an appropriate order under sub. (3).
(3) PROTECTIVE ORDERS. (a) Upon motion by a party or by the person from whom discovery is sought, and for good cause shown, the court may make any order which justice requires to protect a party or person from annoyance, embarrassment, oppression, or undue burden or expense, including but not limited to one or more of the following: 1. That the discovery not be had; 2. That the discovery may be had only by specifying terms, including time and place or the allocation of expenses, for the disclosure or discovery; 3. That the discovery may be had only by a method of discovery other than that selected by the party seeking discovery; 4. That certain matters not be inquired into, or that the scope of the discovery be limited to certain matters; 5. That discovery be conducted with no one present except persons designated by the court; 6. That a deposition after being sealed be opened only by order of the court; 7. That a trade secret, as defined in s. 134.90 (1) (c), or other confidential research, development, or commercial information not be disclosed or be disclosed only in a designated way; 8. That the parties simultaneously file specified documents or information enclosed in sealed envelopes to be opened as directed by the court. (b) If the motion for a protective order is denied in whole or in part, the court may, on such terms and conditions as are just, order that any party or person provide or permit discovery. Section 804.12 (1) (c) applies to the award of expenses incurred in relation to the motion. (c) Motions under this subsection may be heard as prescribed in s. 807.13.
(4) SEQUENCE AND TIMING OF DISCOVERY. Unless the parties stipulate or the court upon motion, for the convenience of parties and witnesses and in the interests of justice, orders otherwise, methods of discovery may be used in any sequence and the fact that a party is conducting discovery, whether by deposition or otherwise, shall not operate to delay any other party’s discovery.
(5) SUPPLEMENTATION OF RESPONSES. A party who has responded to a request for discovery with a response that was complete when made is under no duty to supplement the response to include information thereafter acquired, except as follows:
(a) A party is under a duty seasonably to supplement the party’s response with respect to any question directly addressed to all of the following: 1. The identity and location of persons having knowledge of discoverable matters. 2. The identity of each person expected to be called as an expert witness at trial.
(b) A party is under a duty seasonably to amend a prior response if the party obtains information upon the basis of which 1. the party knows that the response was incorrect when made, or 2. the party knows that the response though correct when made is no longer true and the circumstances are such that a failure to amend the response is in substance a knowing concealment.
(c) A duty to supplement responses may be imposed by order of the court, agreement of the parties, or at any time prior to trial through new requests for supplementation of prior responses.
(6) CUSTODY OF DISCOVERY DOCUMENTS. (a) Unless the court in any action orders otherwise, the original copies of all depositions, interrogatories, requests for admission and responses thereto, and other discovery documentation shall be retained by the party who initiated the discovery or that party’s attorney.
(b) The original copy of a deposition shall be retained by the attorney sealed as received from the person recording the testimony until the appeal period has expired, or until made a part of the record.
(7) RECOVERING INFORMATION INADVERTENTLY DISCLOSED. If information inadvertently produced in discovery is subject to a claim of privilege or of protection as trial preparation material, the party making the claim may notify any party that received the information of the claim and the basis for it. After being notified, a party must promptly return, sequester, or destroy the specified information and any copies it has; must not use or disclose the information until the claim is resolved; must take reasonable steps to retrieve the information if the party disclosed it before being notified; and may promptly present the information to the court under seal for a determination of the claim. The producing party must preserve the information until the claim is resolved.
Official Notes
Judicial Council Note, 1986: Sub. (6) requires that the originals of discovery documents be retained by the party who initiated the discovery, or his or her attorney, unless the court otherwise directs, until the time for appeal has expired. [Re Order eff. 7-1-86.]
Judicial Council Note, 1988: Sub. (3) (c) [created] allows motions for protective orders to be heard by telephone conference. [Re Order effective Jan. 1, 1988]
Judicial Council Note, 1995: The revision to sub. (2) (d) 1. makes it unnecessary to obtain a court order to take an expert’s deposition. By mutual agreement, practitioners commonly agree to take experts’ depositions without troubling the court for an order. The court’s power to control the discovery process is sufficient to prevent abuses. The revision is based on Rule 26 (b) (4) (A), F.R.C.P. Subsection (2) (d) 2. is amended to specify that discovery of non-testifying experts may be made by interrogatories or depositions. The revision is based on Rule 26 (b) (4) (B), F.R.C.P.
Supreme Court Note, 2010: Sub. (2) (e) was created as a measure to manage the costs of the discovery of electronically stored information. If the parties confer before embarking on such discovery, they may reduce the ultimate cost. The rule does not require parties to confer before commencing discovery under s. 804.05 (Depositions upon oral examination), s. 804.06 (Depositions upon written questions), s. 804.08 (Interrogatories to parties); or s. 804.11 (Requests for admission). These discovery devices, if employed before serving a request for production or inspection of electronically stored information, may lead to more informed conferences about the potential scope of such discovery. Parties may not be able to reach consensus on how discovery of electronically stored information is to be managed. Accordingly, subs. (e) 2. and (e) 3. confer authority on the court to intervene as appropriate. In determining whether to issue an order relating to discovery of electronically stored information, the circuit court may compare the costs and potential benefits of discovery. See Vincent & Vincent, Inc. v. Spacek, 102 Wis. 2d 266, 306 N.W.2d 85 (Ct. App. 1981). It is also appropriate to consider the factors specified in the Advisory Committee notes to Fed. R. Civ. P. 26(b)(2)(B): (1) the specificity of the discovery request; (2) the quantity of information available from other and more easily accessed sources; (3) the failure to produce relevant information that seems likely to have existed but is no longer available on more easily accessed sources; (4) the likelihood of finding relevant, responsive information that cannot be obtained from other, more easily accessed sources; (5) predictions as to the importance and usefulness of the further information; (6) the importance of the issues at stake in the litigation; and (7) the parties’ resources.
Judicial Council Note, 2012: Sup. Ct. Order No. 12-03 states that “the Judicial Council Notes to Wis. Stat. § 804.01 (2) (c), 804.01 (7), 805.07 (2) (d), and 905.03 (5) are not adopted, but will be published and may be consulted for guidance in interpreting and applying the rule.” Sub. (2) (c) is amended to make explicit the effect of different kinds of disclosures of trial preparation materials. An inadvertent disclosure of trial preparation materials is akin to an inadvertent disclosure of a communication protected by the lawyerclient privilege. Whether such a disclosure results in a forfeiture of the protection is determined by the same standards set forth in Wis. Stat. s. 905.03(5). A disclosure that is other than inadvertent is treated as a waiver. The distinction between “waiver” and “forfeiture” is discussed in cases such as State v. Ndina, 2009 WI 21, ¶¶28-31, 315 Wis. 2d 653. Sub. (7) is modeled on Fed. R. Civ. P. 26(b)(5)(B), the so-called “clawback” provision of the federal rules. The following Committee Note of the federal Advisory Committee on Civil Rules regarding the 2006 Amendments to the Federal Rules of Civil Procedure (regarding discovery of electronically stored information) is instructive in understanding the scope and purpose of Wisconsin’s version: The Committee has repeatedly been advised that the risk of privilege waiver, and the work necessary to avoid it, add to the costs and delay of discovery. When the review is of electronically stored information, the risk of waiver, and the time and effort required to avoid it, can increase substantially because of the volume of electronically stored information and the difficulty in ensuring that all information to be produced has in fact been reviewed. Rule 26(b)(5)(A) provides a procedure for a party that has withheld information on the basis of privilege or protection as trial-preparation material to make the claim so that the requesting party can decide whether to contest the claim and the court can resolve the dispute. Rule 26(b)(5)(B) is added to provide a procedure for a party to assert a claim of privilege or trial-preparation material protection after information is produced in discovery in the action and, if the claim is contested, permit any party that received the information to present the matter to the court for resolution. Rule 26(b)(5)(B) does not address whether the privilege or protection that is asserted after production was waived by the production. The courts have developed principles to determine whether, and under what circumstances, waiver results from inadvertent production of privileged or protected information. Rule 26(b)(5)(B) provides a procedure for presenting and addressing these issues. Rule 26(b)(5)(B) works in tandem with Rule 26(f), which is amended to direct the parties to discuss privilege issues in preparing their discovery plan, and which, with amended Rule 16(b), allows the parties to ask the court to include in an order any agreements the parties reach regarding issues of privilege or trial-preparation material protection. Agreements reached under Rule 26(f)(4) and orders including such agreements entered under Rule 16(b)(6) may be considered when a court determines whether a waiver has occurred. Such agreements and orders ordinarily control if they adopt procedures different from those in Rule 26(b)(5)(B). A party asserting a claim of privilege or protection after production must give notice to the receiving party. That notice should be in writing unless the circumstances preclude it. Such circumstances could include the assertion of the claim during a deposition. The notice should be as specific as possible in identifying the information and stating the basis for the claim. Because the receiving party must decide whether to challenge the claim and may sequester the information and submit it to the court for a ruling on whether the claimed privilege or protection applies and whether it has been waived, the notice should be sufficiently detailed so as to enable the receiving party and the court to understand the basis for the claim and to determine whether waiver has occurred. Courts will continue to examine whether a claim of privilege or protection was made at a reasonable time when delay is part of the waiver determination under the governing law. After receiving notice, each party that received the information must promptly return, sequester, or destroy the information and any copies it has. The option of sequestering or destroying the information is included in part because the receiving party may have incorporated the information in protected trial-preparation materials. No receiving party may use or disclose the information pending resolution of the privilege claim. The receiving party may present to the court the questions whether the information is privileged or protected as trial-preparation material, and whether the privilege or protection has been waived. If it does so, it must provide the court with the grounds for the privilege or protection specified in the producing party’s notice, and serve all parties. In presenting the question, the party may use the content of the information only to the extent permitted by the applicable law of privilege, protection for trial-preparation material, and professional responsibility. If a party disclosed the information to nonparties before receiving notice of a claim of privilege or protection as trial-preparation material, it must take reasonable steps to retrieve the information and to return it, sequester it until the claim is resolved, or destroy it. Whether the information is returned or not, the producing party must preserve the information pending the court’s ruling on whether the claim of privilege or of protection is properly asserted and whether it was waived. As with claims made under Rule 26(b)(5)(A), there may be no ruling if the other parties do not contest the claim.
Plain-English Summary
Parties may use depositions on oral examination or written questions, written interrogatories, production or inspection of documents, land, or things, physical and mental examinations, and requests for admission, and by default the frequency of these methods is not limited, subject to a court order or the specific caps set elsewhere in the chapter. Discoverable material must be nonprivileged, relevant to a claim or defense, and proportional to the case, weighing the stakes involved, the amount in controversy, each side’s access to information and resources, how important the discovery is to resolving the issues, and whether its burden or expense outweighs its likely benefit; on motion, the court must limit discovery that is cumulative, more easily obtained elsewhere, or disproportionate. Insurance agreements are discoverable, though disclosure alone does not make them admissible, and a party must disclose, without waiting for a request, any agreement giving someone other than a permitted contingent-fee attorney a right to compensation contingent on and sourced from the case’s proceeds.
Trial-preparation materials get a qualified shield: the requesting party generally must show substantial need and an inability to get the substantial equivalent elsewhere without undue hardship, and even then the court protects an attorney’s or representative’s mental impressions, conclusions, opinions, and legal theories, a protection that can be forfeited through inadvertent disclosure or waived through a deliberate one. A party can, without that showing, get its own prior statements, and a nonparty can request its own prior statements too. Discovery of a testifying expert’s facts and opinions proceeds through interrogatories identifying the expert and then a deposition, with further discovery available on court order; reaching a non-testifying, specially retained expert requires a motion showing exceptional circumstances that make it impracticable to get the same facts or opinions elsewhere, and the requesting party typically pays the expert’s fee for the time spent responding, along with a fair share of the other side’s expert-related costs where required.
Electronically stored information carries its own tiered rules: categories like hard-to-retrieve data, duplicative backups, unreadable legacy data, and other not-reasonably-accessible sources require a showing of substantial need and good cause, weighed against proportionality; and before serving an ESI production request or responding to an interrogatory with ESI, the parties generally must confer about the scope of needed discovery, preservation, the form of production, privilege procedures, cost, and phasing, with the court available to resolve disputes if the parties cannot agree or later contest a specific request.
The court can issue protective orders shielding a party or nonparty from annoyance, embarrassment, oppression, or undue burden or expense, ranging from barring the discovery to limiting its scope, method, timing, or the people present, up to protecting trade secrets or requiring sealed submissions; denying a protective order in whole or in part can itself lead to an order compelling discovery on just terms. Discovery methods can proceed in any sequence, and one party’s discovery does not delay another’s, absent a stipulation or court order otherwise. Parties have an ongoing duty to supplement responses about who has knowledge of discoverable matters and who will testify as an expert, and to correct a response they later learn was wrong or is no longer true if silence would amount to knowing concealment. Discovery documents are normally kept by the party who requested them, with deposition originals sealed until the appeal period runs or the deposition becomes part of the record. And if privileged material is produced by mistake, the producing party can notify the recipient of the claim, after which the recipient must promptly return, sequester, or destroy the material, stop using or disclosing it, and take reasonable steps to retrieve any copies already shared, while the producing party preserves the material until the claim is resolved.
Frequently Asked Questions
What discovery methods are available in a Wisconsin civil case?
Depositions on oral examination or written questions, written interrogatories, production or inspection of documents, land, or things, physical and mental examinations, and requests for admission.
What makes information discoverable under Wisconsin’s proportionality standard?
It must be nonprivileged, relevant to a party’s claim or defense, and proportional to the case considering the stakes, the amount in controversy, each side’s access to information and resources, and whether the burden or expense outweighs the likely benefit.
Can I get the other side’s litigation funding or contingent-fee-style agreements without asking?
Yes. Section 804.01(2)(bg) requires a party to disclose, without waiting for a discovery request, any agreement giving someone other than a permitted contingent-fee attorney a right to compensation contingent on and sourced from the case’s proceeds.
What protects my attorney’s mental impressions and strategy from discovery?
Trial-preparation materials generally require the requesting party to show substantial need and undue hardship in obtaining the equivalent elsewhere, and even then the court must protect an attorney’s mental impressions, conclusions, opinions, and legal theories.
What do I have to do if I accidentally produce privileged documents in discovery?
Under section 804.01(7), notify the receiving party of the claim; once notified, that party must promptly return, sequester, or destroy the material, stop using or disclosing it, and take reasonable steps to retrieve any copies already shared, while you preserve the material until the claim is resolved.
Amendment History
History: Sup. Ct. Order, 67 Wis. 2d 585, 654 (1975); 1975 c. 218; 1985 a. 236; Sup. Ct. Order, 130 Wis. 2d xix (1986); Sup. Ct. Order, 141 Wis. 2d xiii (1987); 1993 a. 486; Sup. Ct. Order No. 95-03, 191 Wis. 2d xix (1995); 1997 a. 35, 133; 2007 a. 20; Sup. Ct. Order No. 09-01, 2010 WI 67, filed 7-6-10, eff. 1-1-11; Sup. Ct. Order No. 09-01A, 2010 WI 129, 329 Wis. 2d xix; Sup. Ct. Order No. 12-03, 2012 WI 114, 344 Wis. 2d xxi; 2015 a. 55; 2017 a. 235.
Source & verification. Section text and official notes are
reproduced verbatim from the Wisconsin Statutes, published by the
Wisconsin Legislature (Legislative Reference Bureau). Last verified July 15, 2026.
· Official source
Also known as: wisconsin discovery scope and limitsproportionality standard discovery wisconsinprotective order wisconsin lawsuitclawback privileged documents wisconsinelectronically stored information discovery wisconsin