§ 17.1the blackletter · sectionp. 25

§ 17.1  Discovery: Liberal Policy; No Good-Cause Showing for Routine Requests

● settled · en banc · quotations verified 8/24/26 · cite: Blackletter § 17.1, p. 25 (2026) ·
“Our holding herein is consistent with the public policy favoring liberal pre-trial discovery that may reasonably lead to relevant and admissible evidence applicable in workers’ compensation cases.”

(DiFusco, supra, at p. 15, citing Allison v. Workers’ Comp. Appeals Bd. (1999) 72 Cal.App.4th 654, 663.)

“We emphasize that in workers’ compensation proceedings, the Labor Code makes explicit that the WCJ and the Appeals Board have greater discretion with respect to evidentiary matters than courts in civil proceedings, and not narrower discretion as defendant appears to believe.”

(DiFusco, supra, at p. 15.)

“Section 5708 mandates that we are not “bound by the common law or statutory rules of evidence and procedure, but may make inquiry in the manner, through oral testimony and records, which is best calculated to ascertain the substantial rights of the parties and carry out justly the spirit and provisions of this division.””

(DiFusco, supra, at p. 15, quoting Lab. Code, § 5708.)

“Section 5709 specifically allows informality in our proceedings and ensures that “admission into the record, and use as proof of any fact in dispute, of any evidence not admissible under the common law or statutory rules of evidence and procedure” will not invalidate an order, decision or award.”

(DiFusco, supra, at p. 15, citing Lab. Code, § 5709.)

“Unlike a discovery request where the right to privacy or another privilege is implicated, proof of good cause is not required for a routine discovery request such as the one here.”

(DiFusco, supra, at p. 15.)

“[A]pplicant has a right to the insurance coverage information and potentially liable parties purely by way of a discovery request for relevant information, even without the consideration of the specific disclosure requirements detailed herein.”

(DiFusco, supra, at p. 15.)

“Under the Civil Discovery Act, discovery is generally available “regarding any matter, not privileged, that is relevant to the subject matter involved in the pending action or to the determination of any motion made in that action. . . .””

(DiFusco, supra, at p. 15, fn. 13, quoting Code Civ. Pro., § 2017.101 [sic; see Code Civ. Proc., § 2017.010].)

“The underlying principle of liberal discovery supports our duty to ensure substantial justice and to further develop the record where there is insufficient evidence on an issue.”

(DiFusco, supra, at p. 15, fn. 12, citing Kuykendall v. Workers’ Comp. Appeals Bd. (2000) 79 Cal.App.4th 396, 403; McClune v. Workers’ Comp. Appeals Bd. (1998) 62 Cal.App.4th 1117, 1121–1122.)

“The Appeals Board may not leave matters undeveloped where it is clear that additional discovery is needed.”

(DiFusco, supra, at p. 15, fn. 12, citing Kuykendall, supra, at p. 404.)

“All hearings and investigations before the appeals board or a workers’ compensation judge are governed by this division and by the rules of practice and procedures adopted by the appeals board. In the conduct thereof they shall not be bound by the common law or statutory rules of evidence and procedure, but may make inquiry in the manner, through oral testimony and records, which is best calculated to ascertain the substantial rights of the parties and carry out justly the spirit and provisions of this division. All oral testimony, objections, and rulings shall be taken down in shorthand by a competent phonographic reporter.”

(Lab. Code, § 5708, as quoted in full in Perez, supra, at p. 8.)

“No informality in any proceeding or in the manner of taking testimony shall invalidate any order, decision, award, or rule made and filed as specified in this division. No order, decision, award, or rule shall be invalidated because of the admission into the record, and use as proof of any fact in dispute, of any evidence not admissible under the common law or statutory rules of evidence and procedure.”

(Lab. Code, § 5709, as quoted in full in Perez, supra, at p. 9.)

Cross-references: § 16.2 (the Coldiron disclosures); § 22.1 (insurance policy information); § 20.1 (the admitted record).

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California Workers’ Compensation Blackletter (2026)25