The California Rules of Evidence are codified in the California Evidence Code, and they govern what judges and juries in state superior courts are allowed to hear during civil, criminal, family, and probate trials. The Code sets the standards for relevance, hearsay, privilege, character evidence, expert testimony, and authentication. Some rules track federal evidentiary law closely. Others — particularly on expert opinion, hearsay exceptions, and prior sexual or domestic violence offenses — depart from it in ways that matter to anyone involved in a California case.
The Code controls trial proceedings and formal evidentiary hearings. Administrative hearings, arbitrations, and pretrial motions like summary judgment operate under looser standards and often rely on declarations that would not survive at trial.
One constitutional overlay shapes everything in criminal court. Proposition 8, passed by voters in 1982 and now found in Article I, Section 28 of the California Constitution, requires courts to admit all relevant evidence in criminal cases unless the U.S. Constitution, a two-thirds legislative vote, or a specific statutory exception (such as privilege, hearsay, or Evidence Code 352) demands exclusion.1California Legislative Information. California Constitution Article I Section 28 In practice, California criminal courts lean toward admitting relevant evidence more broadly than courts in some other states.
Relevance and the Section 352 Balancing Test
Every piece of evidence has to clear relevance first. Evidence Code 210 defines relevant evidence as anything with a tendency to prove or disprove a disputed fact of consequence to the case.2California Legislative Information. California Code Evidence Code 210 – Relevant Evidence The bar is low. Evidence doesn’t have to prove anything conclusively; it just has to move the needle. Medical records documenting a plaintiff’s injuries clear that threshold in a personal injury case. Records about an unrelated condition from years earlier would not.
Relevant evidence can still be excluded. Under Evidence Code 352, a judge may keep out evidence whose probative value is substantially outweighed by the risk of undue prejudice, confusion of the issues, or waste of time.3California Legislative Information. California Code Evidence 352 – Admitting and Excluding Evidence Graphic crime scene photographs are the classic example. If the images are more likely to inflame than to inform, the judge has discretion to exclude them. Section 352 comes up constantly, and trial judges have wide latitude in applying it.
Burdens of Proof
Whoever asserts a claim carries the burden of proving it. Evidence Code 115 recognizes three standards of proof.4California Legislative Information. California Code EVID 115 – Burden of Proof
- Preponderance of the evidence is the default in civil cases. The party with the burden wins if its version is more likely true than not.
- Clear and convincing proof applies to fraud claims, punitive damages, and certain family law matters. The evidence must make the fact highly probable.
- Beyond a reasonable doubt applies only in criminal prosecutions. The prosecution must eliminate any reasonable doubt about the defendant’s guilt.
Presumptions also do a lot of work in California trials. Under Evidence Code 600, a presumption is an assumption of fact the law requires once a foundational fact is established, and it is not itself evidence.5California Legislative Information. California Evidence Code Section 600 Some presumptions shift the burden of producing contrary evidence. Others are conclusive and cannot be rebutted at all.
Character Evidence and Prior Bad Acts
Evidence Code 1101(a) bars propensity evidence. A party cannot use a person’s character — proven through reputation, opinion, or past conduct — to argue the person acted in conformity with that character on a particular occasion.6California Legislative Information. California Code EVID 1101 – Character Evidence A prosecutor can’t offer a defendant’s prior theft to argue the defendant is “the type of person” who steals.
The exceptions do a lot of work. Section 1101(b) allows prior-act evidence when offered to prove something other than character: motive, intent, preparation, plan, knowledge, identity, or absence of mistake. If a defendant claims they didn’t know a substance they were carrying was illegal, a prior similar offense may come in to prove knowledge. The line between “proving character” and “proving intent” is where most of the arguments happen.
California carves out a much broader exception for sexual offenses. Evidence Code 1108 allows prosecutors to introduce evidence that a defendant committed other sexual offenses — including to show propensity — provided the evidence survives section 352 balancing.7California Legislative Information. California Code EVID 1108 – Sexual Offense Evidence Evidence Code 1109 provides a parallel exception in domestic violence cases. Both are deliberate departures from the general ban on propensity evidence.
Hearsay
Hearsay is the most litigated evidentiary issue in California courts. Evidence Code 1200 defines it as a statement made outside the courtroom offered to prove that what the statement says is true.8California Legislative Information. California Code EVID 1200 – Hearsay Evidence The concern is reliability. If a witness testifies that a neighbor said the defendant was speeding, the jury cannot cross-examine the neighbor to test that claim.
Not every out-of-court statement counts as hearsay. A statement offered to show its effect on the listener — rather than to prove its content — is not hearsay. In a fraud case, testimony that the defendant called an investment “guaranteed” can be admitted to show the victim relied on that statement, not to prove the investment was safe. Statements that themselves form a legal act, like the words of a contract or a threat, also fall outside the rule.
Key Hearsay Exceptions
California recognizes dozens of exceptions, each resting on a judgment that certain kinds of statements carry enough built-in reliability. A handful come up most often.
Spontaneous statements. Evidence Code 1240 admits a statement describing something the speaker just perceived, made while still under the stress of excitement from that event.9California Legislative Information. California Code EVID 1240 – Spontaneous Statement The theory is that a person blurting out what just happened has no time to fabricate. There is no fixed time cutoff; courts have admitted statements made hours later where the speaker was still in the agitated state.
Dying declarations. Evidence Code 1242 admits a statement about the cause and circumstances of a person’s death when the speaker had personal knowledge and believed death was imminent.10California Legislative Information. California Evidence Code 1242
Prior inconsistent statements. Under Evidence Code 1235, if a witness testifies one way at trial but said something different before, the earlier statement can come in as substantive evidence, provided questioning follows section 770’s procedures.11California Legislative Information. California Code Evidence Code – EVID 1235 Unlike in some other jurisdictions, California juries may treat the prior statement as evidence of the facts it describes, not just as impeachment.
Declarations against interest. Evidence Code 1230 admits a statement by an unavailable declarant that was so damaging to the speaker’s financial, legal, or social interests that no reasonable person would have made it unless it was true.12California Legislative Information. California Code EVID 1230 – Declaration Against Interest
Business records. Evidence Code 1271 admits records kept in the ordinary course of business if they were made at or near the time of the event, a qualified witness can describe how they were prepared, and the circumstances suggest trustworthiness.13California Legislative Information. California Code EVID 1271 – Business Records Medical records, corporate financials, and inventory logs typically come in this way. Records prepared specifically for litigation do not qualify.
Privileges
Certain confidential communications are protected even when relevant. Each privilege has its own scope and its own exceptions.
Attorney-Client
Evidence Code 950 through 962 protect confidential communications between a lawyer and client made to obtain legal advice, covering oral and written communications and extending to staff and interpreters. The privilege belongs to the client, survives the end of the relationship, and can only be waived by the client, including through voluntary disclosure to outsiders.14Justia. California Code Evidence Code 950-962 – Lawyer-Client Privilege Under section 956, the privilege disappears when the client sought legal help to commit a crime or fraud. It also doesn’t apply in disputes between the attorney and client, such as a malpractice suit.
Spousal Privileges
California recognizes two distinct spousal privileges, and they are easy to confuse. The spousal testimonial privilege under Evidence Code 970 lets a married person refuse to testify against their spouse in any proceeding, criminal or civil. It exists only during the marriage and belongs to the witness spouse.15California Legislative Information. California Code EVID 970 – Privilege Not to Testify Against Spouse
The marital communications privilege, in Evidence Code 980 through 987, protects the substance of confidential communications between spouses and survives divorce.16California Legislative Information. California Evidence Code – Privilege Not to Testify Against Spouse Both privileges give way when one spouse is charged with a crime against the other spouse or against a child.
Physician-Patient
Evidence Code 990 through 1007 allow patients to prevent disclosure of confidential communications with a licensed physician, psychologist, or psychotherapist made for diagnosis or treatment, including records and clinical notes.17Justia. California Code 990-1007 – Physician-Patient Privilege Several exceptions can override it. Under section 996, the privilege does not apply when the patient’s condition is at issue in the litigation, as when a plaintiff seeks damages for a personal injury.18California Legislative Information. California Evidence Code 996 The privilege also does not apply in criminal proceedings under section 998, or where the patient sought services to help commit a crime or tort under section 997. Physicians may also be required to disclose under mandatory reporting laws (such as those covering child abuse) and under the Tarasoff duty to warn when a patient poses a serious threat to others.
Clergy-Penitent
Evidence Code 1030 through 1034 protect penitential communications made in confidence to a member of the clergy who is authorized by their faith to hear such communications and has a duty to keep them secret.19California Legislative Information. California Evidence Code 1030-1034 – Clergy-Penitent Privilege Both the penitent and the clergy member independently hold the privilege, so either can refuse to disclose.
Witness Testimony and Credibility
Every witness must clear two competency requirements before taking the stand: the ability to communicate clearly enough to be understood, and the ability to understand the duty to tell the truth, under Evidence Code 701. Personal knowledge — actually having perceived what the witness describes — is a separate requirement under section 702.20California Legislative Information. California Evidence Code – Division 6 – Witnesses
Once a witness testifies, credibility is the central question. Evidence Code 780 lists factors the trier of fact may weigh: demeanor, opportunity to observe, bias or motive to lie, prior inconsistent statements, and admissions of untruthfulness.21California Legislative Information. California Code EVID 780 – Credibility In criminal trials, the defendant’s right to confront and cross-examine witnesses is guaranteed by both the Sixth Amendment and Article I, Section 15 of the California Constitution.22Justia. California Constitution Article I Section 15 – Declaration of Rights
Expert Testimony
Experts can offer opinions and conclusions based on their training, not just perceptions. Evidence Code 801 limits expert testimony to subjects sufficiently beyond common experience that the opinion would help the jury, and requires the opinion to rest on material an expert in the field would reasonably rely on.23California Legislative Information. California Code EVID 801 – Opinion Testimony by Expert Witness
Kelly/Frye for Novel Science
When an expert relies on a new or novel scientific methodology, California applies the Kelly/Frye standard from People v. Kelly (1976), which requires general acceptance of the methodology in the relevant scientific community.24Justia. People v. Kelly, 17 Cal. 3d 24 California has not adopted the federal Daubert standard, which gives judges broader discretion to weigh methodology directly. Kelly/Frye governs novel science in California state courts.
Sargon and the Gatekeeping Duty
For expert testimony more broadly, the California Supreme Court’s 2012 decision in Sargon Enterprises, Inc. v. University of Southern California requires trial judges to act as gatekeepers. A court must exclude expert opinion that is speculative, based on material an expert cannot reasonably rely on, or grounded in reasoning unsupported by the expert’s own data.25Justia. Sargon Enters., Inc. v. Univ. of S. Cal. Before Sargon, many judges were reluctant to exclude expert testimony, reasoning that flawed logic was cross-examination’s problem. Sargon closed that door.
Sanchez and Case-Specific Hearsay
The 2016 decision in People v. Sanchez changed how experts can use out-of-court information. The California Supreme Court held that when an expert relates case-specific facts drawn from hearsay sources and treats those facts as true to support the opinion, those statements are hearsay and must either be independently proven or fall within a recognized exception.26Justia. People v. Sanchez – 2016 California Case Law Experts had routinely testified about the contents of police reports, lab results, and other documents they did not personally create. That practice is now significantly constrained. If the hearsay is also testimonial (made primarily for use in prosecution), admitting it without the declarant available for cross-examination also violates the Confrontation Clause.
Authentication and Digital Evidence
Before any document, photograph, or recording is admitted, the offering party has to authenticate it — prove it is what they say it is. Evidence Code 1400 defines authentication as introducing enough evidence to support a finding that the item is genuine, whether through witness testimony, circumstantial evidence, or other permitted methods.27California Legislative Information. California Code EVID 1400 – Authentication of a Writing Section 1401 makes authentication a prerequisite; no writing comes in without it.28California Legislative Information. California Code Evidence Code 1401 – Requirement of Authentication
For a contract, a witness confirming the signature usually suffices. For a photograph, someone at the scene can testify that the image accurately depicts what they saw. Digital evidence is harder. Courts look at identifying characteristics like email addresses, phone numbers, timestamps, and metadata. Testimony from the sender or recipient often supplies the foundation, and where no such witness is available, forensic analysis of the device or account may be needed. In People v. Beckley (2010), a California Court of Appeal held that the prosecution’s failure to properly authenticate a photograph and document downloaded from the internet should have barred their admission.29FindLaw. People v. Beckley In criminal cases, chain-of-custody documentation for digital items is critical to defeating claims of tampering.
Judicial Notice
Not everything at trial has to be proven with testimony and exhibits. Under Evidence Code 452, courts can take judicial notice of facts either commonly known in the jurisdiction or capable of immediate and accurate determination from reliable sources — the day of the week a date fell on, for example, or an interest rate published by a government agency.30California Legislative Information. California Code Evidence Code – EVID 452 Courts must also take judicial notice of the decisional and statutory law of any U.S. state, federal regulations, and official acts of government bodies. A party asking for judicial notice of less obvious facts should supply the court with enough information to verify them from an indisputably accurate source.