Not just because counsel consulted an expert. California’s reciprocal discovery statute generally reaches an expert whom the defense intends to call at trial, along with relevant statements or reports and test results the defense intends to offer. A consulting-only expert is not automatically disclosed merely because counsel investigated the case with that person. The exact witness role, proposed testimony, material, and any privilege or work-product issue matter. (Penal Code § 1054.3; Izazaga v. Superior Court)
Distinguish consultation from expected trial testimony
Section 1054.3 requires disclosure of intended defense trial witnesses and relevant statements or reports of those witnesses, including expert reports, as well as scientific test results the defense intends to offer. California’s Supreme Court has explained that the intended-witness trigger includes witnesses reasonably anticipated as likely to be called. Merely consulting an expert who is not expected to testify does not, by itself, trigger disclosure under that rule. (Penal Code § 1054.3; Izazaga)
The trigger is not simply who paid for an evaluation or whether a document has “draft” in its filename. Counsel should identify whether the expert is likely to testify, which opinions or results may be offered, what statements or reports relate to that testimony, and whether a document includes protected attorney analysis or privileged communications. A report may contain both expert material and counsel’s protected work; counsel must assess the actual contents rather than assume every page is either discoverable or immune.
Work product and timing have limits
Penal Code section 1054.6 protects core attorney work product—writings reflecting counsel’s impressions, conclusions, opinions, legal research, or theories—and preserves express privileges. It is not a blanket shield for every document created during an expert consultation. California decisions distinguish core written attorney work product from a generic claim that all expert contact or reports are protected. (Penal Code § 1054.6; Code Civ. Proc. § 2018.030; People v. Nadey)
For covered material, section 1054.7 generally requires disclosure at least 30 days before trial, or immediately if the material first becomes known to or possessed by a party within 30 days of trial. Good cause for denial, restriction, or delay is limited to threats or possible danger to a victim or witness, possible loss or destruction of evidence, or possible compromise of another law-enforcement investigation. These exceptions are handled through the legal process; they are not a reason to conceal, alter, or destroy reports. (Penal Code § 1054.7)
Keep the engagement scope, expert communications, report versions, test results, expected trial date, and any protective order for counsel to review. Mental-health examinations can involve separate provisions under section 1054.3(b); this page addresses ordinary expert discovery, not those distinct procedures. Do not decide on your own to withhold or disclose disputed material.
The Law Offices of David S. Chesley represents people facing California criminal charges. Call (800) 755-5174 to discuss expert evidence and discovery duties.