The California Rules of Evidence are the admissibility standards set out in the California Evidence Code, and they decide what a judge or jury can actually consider in a trial. The Code applies in civil lawsuits, criminal prosecutions, family law disputes, and probate matters in the state’s superior courts. Its rules cover relevance, hearsay, privileges, authentication, witness competency, expert opinion, and burdens of proof. If a piece of information can’t clear those rules, it stays out, no matter how useful it might sound.
Some California rules track federal evidence law closely. Others don’t. Expert testimony, hearsay exceptions, and the treatment of prior bad acts are areas where California has gone its own way, and understanding those differences matters for anyone involved in a California case.
Where the Code Applies
The Evidence Code governs every stage of trial where facts are presented to the court. Administrative hearings and arbitration proceedings run on more relaxed procedural guidelines. Pretrial motions like summary judgment rely on declarations and affidavits that don’t have to meet full trial evidentiary standards. So the full force of the rules below is a trial-court phenomenon.
Constitutional protections sit on top of the Code, especially in criminal cases. Article I, Section 13 of the California Constitution mirrors the Fourth Amendment, and evidence obtained in violation of those protections can be excluded.1Justia. California Constitution Article I Section 13 – Declaration of Rights Pulling the other direction, Proposition 8’s “Truth-in-Evidence” provision in Article I, Section 28 requires California criminal courts to admit all relevant evidence 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.2California Legislative Information. California Constitution Article I Section 28 The practical effect is that California criminal courts lean toward admitting relevant evidence more broadly than some other states.
Relevance and the Section 352 Balancing Test
The first hurdle for any piece of evidence is relevance. Evidence Code 210 defines relevant evidence as anything with a tendency to prove or disprove a disputed fact that matters to the outcome.3California Legislative Information. California Code Evidence Code 210 – Relevant Evidence The bar is deliberately low. Evidence doesn’t have to prove a fact; it just has to move the needle. In a personal injury case, medical records tied to the plaintiff’s injuries clear the threshold easily. Records about an unrelated condition from years earlier do not.
Relevant evidence can still be excluded. Under Evidence Code 352, a judge can exclude evidence whose probative value is substantially outweighed by the risk of wasting time, confusing the issues, or unfairly prejudicing the jury.4California 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 can keep them out. This balancing test comes up constantly, and judges have broad latitude in applying it.
One specific exclusionary rule is worth flagging. Evidence Code 1151 bars evidence of repairs or safety improvements made after an accident when offered to prove negligence.5California Legislative Information. California Code Evidence Code – EVID 1151 If a property owner fixes a broken staircase after a fall, the repair itself can’t be used at trial to show fault. The policy is to avoid discouraging safety improvements by turning them into courtroom admissions.
Burdens of Proof
Every party asserting a claim or defense carries a burden of proof. Evidence Code 115 recognizes three standards.6California Legislative Information. California Code EVID 115 – Burden of Proof
- Preponderance of the evidence is the civil default. You win if your version is more likely true than not.
- Clear and convincing proof applies in certain civil matters like fraud claims, punitive damages, and some family law proceedings. The evidence must make the fact highly probable.
- Beyond a reasonable doubt is reserved for criminal prosecutions. The prosecution must eliminate any reasonable doubt about the defendant’s guilt.
California also leans on presumptions. Under Evidence Code 600, a presumption is an assumption of fact required by law once another fact is proven, and the presumption itself is not evidence.7California Legislative Information. California Evidence Code Section 600 Some presumptions shift the burden to the opposing side to produce contrary evidence. Others are conclusive and can’t be rebutted at all. Which type applies can decide how a case gets tried.
Character Evidence and Prior Acts
Evidence Code 1101(a) prohibits using evidence of a person’s character, whether through reputation, opinion, or past conduct, to argue they acted in conformity with that character on a particular occasion.8California Legislative Information. California Code EVID 1101 – Character Evidence A prosecutor can’t present a prior theft to argue the defendant is “the type of person” who steals.
The exceptions matter as much as the rule. Section 1101(b) allows evidence of prior acts when offered to prove something other than character, such as motive, intent, preparation, plan, knowledge, identity, or absence of mistake. If a defendant claims they didn’t know a substance was illegal, the prosecution may introduce a prior similar offense to show knowledge. The line between “proving character” and “proving intent” is where many evidentiary fights happen.
California also carves out broader exceptions for certain charges. Evidence Code 1108 allows prosecutors to introduce evidence that a defendant committed other sexual offenses, even to show propensity, as long as the evidence survives the section 352 balancing test.9California Legislative Information. California Code EVID 1108 – Sexual Offense Evidence A similar exception exists under Evidence Code 1109 for domestic violence cases. These are deliberate departures from the general ban on propensity evidence.
Hearsay
Hearsay is probably the most litigated evidentiary issue in California courts. Evidence Code 1200 defines it as a statement someone made outside the courtroom that a party offers to prove that what the statement says is true.10California Legislative Information. California Code EVID 1200 – Hearsay Evidence The concern is reliability. If a witness tells the jury “my neighbor told me the defendant was speeding,” the jury can’t cross-examine the neighbor to test the claim. That’s why hearsay is generally excluded.
Not every out-of-court statement is hearsay, and this is where people get tripped up. A statement offered to show its effect on the listener, rather than to prove what the statement says, is not hearsay. In a fraud case, testimony that the defendant said an investment was “guaranteed” can come in to show the victim relied on that statement, not to prove the investment was actually safe. Statements that function as part of a legal act, like words forming a contract or constituting a threat, also fall outside the hearsay rule.
Spontaneous Statements and Dying Declarations
Under Evidence Code 1240, a statement is admissible if the person who made it was describing something they just perceived while still under the stress of excitement caused by that event.11California Legislative Information. California Code EVID 1240 – Spontaneous Statement The theory is that someone blurting out what happened in the heat of the moment doesn’t have time to fabricate. Courts look at whether the person was still in that agitated state when they spoke. There’s no fixed time limit, and some courts have admitted statements made hours after the event.
Evidence Code 1242 allows a statement about the cause and circumstances of a person’s death if the person made the statement based on personal knowledge while believing death was imminent.12California Legislative Information. California Evidence Code 1242 The rationale, that a person facing death has little reason to lie, is one of the oldest in evidence law.
Prior Inconsistent Statements
If a witness testifies one way at trial but said something different before, the earlier statement can come in as substantive evidence under Evidence Code 1235, provided the questioning follows the procedural requirements of section 770.13California Legislative Information. California Code Evidence Code – EVID 1235 In California, unlike some jurisdictions, the prior statement isn’t limited to impeachment. The jury can treat it as evidence of the facts it describes.
Declarations Against Interest
When a person unavailable to testify previously made a statement so damaging to their own financial, legal, or social interests that no reasonable person would have made it unless they believed it was true, that statement is admissible under Evidence Code 1230.14California Legislative Information. California Code EVID 1230 – Declaration Against Interest The self-harming nature of the statement is what gives it credibility.
Business Records
Records kept in the ordinary course of business are admissible under Evidence Code 1271 if they were created at or near the time of the event they document, a qualified witness can describe how they were prepared, and the circumstances of their creation suggest they are trustworthy.15California Legislative Information. California Code EVID 1271 – Business Records Medical records, corporate financials, and routine inventory logs commonly enter evidence this way. The key is that the record was made as part of a regular business practice, not prepared for litigation.
Privileges
Certain relationships are protected from forced disclosure even when the communications would be relevant.
Attorney-Client
The attorney-client privilege, codified in Evidence Code 950 through 962, protects confidential communications between a lawyer and their client made for the purpose of obtaining legal advice. It covers oral and written communications and extends to the lawyer’s staff and interpreters. The privilege belongs to the client, survives the end of the relationship, and can only be waived by the client, including by voluntarily sharing the information with an outsider.16Justia. California Code Evidence Code 950-962 – Lawyer-Client Privilege Under Evidence Code 956, the privilege disappears when the client sought legal services to help commit a crime or fraud, and it does not apply in disputes between attorney and client, such as a malpractice case where the communication is itself at issue.
Spousal Privileges
California has two spousal privileges that 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, not just criminal cases. It exists only during the marriage and belongs to the witness-spouse, who decides whether to invoke it.17California Legislative Information. California Code EVID 970 – Privilege Not to Testify Against Spouse
The marital communications privilege, in Evidence Code 980 through 987, is different. It protects the substance of confidential communications between spouses and survives divorce. Neither spouse can be forced to reveal what they told each other in confidence during the marriage, even after it ends.18California Legislative Information. California Evidence Code – Privilege Not to Testify Against Spouse Both privileges have exceptions for cases where one spouse is charged with a crime against the other spouse or a child.
Physician-Patient and Psychotherapist
Under Evidence Code 990 through 1007, patients can prevent disclosure of confidential medical information shared with a physician for diagnosis or treatment. The privilege covers licensed physicians, psychologists, and psychotherapists, including medical records and clinical notes.19Justia. California Code 990-1007 – Physician-Patient Privilege Several exceptions override it. Under Evidence Code 996, the privilege doesn’t apply when the patient’s own physical or mental condition is directly at issue, so a plaintiff claiming personal injury damages opens up medical records relevant to that injury.20California Legislative Information. California Evidence Code 996 There is also no privilege in criminal proceedings under Evidence Code 998, or where the patient sought services to help commit a crime or tort under Evidence Code 997. Mandatory reporting laws (such as child abuse reporting) and the Tarasoff duty to warn can also require disclosure.
Clergy-Penitent
Confidential communications made during religious confession or counseling are protected under Evidence Code 1030 through 1034. A “penitential communication” is one 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.21California 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 disclosure.
Witness Testimony and Credibility
Before someone takes the stand, they must meet two basic competency requirements under Evidence Code 701: the ability to communicate clearly enough to be understood, and the ability to understand the duty to tell the truth. Evidence Code 702 adds the requirement of personal knowledge, meaning the witness actually perceived what they’re testifying about.22California Legislative Information. California Evidence Code – Division 6 – Witnesses
Once a witness testifies, credibility becomes the central question. Evidence Code 780 gives courts and juries wide latitude to evaluate truthfulness and lists factors like demeanor, opportunity to observe the events, bias or motive to lie, prior inconsistent statements, and whether the witness has admitted to being untruthful.23California Legislative Information. California Code EVID 780 – Credibility Cross-examination is the main tool for testing these factors. 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.24Justia. California Constitution Article I Section 15 – Declaration of Rights
Expert Opinion
Experts occupy a unique position in California trials. Unlike ordinary witnesses, they can offer opinions and draw conclusions based on specialized training rather than personal observation. Evidence Code 801 limits expert testimony to subjects sufficiently beyond common experience that the opinion would actually help the jury, and requires the opinion to be based on material an expert in the field would reasonably rely on.25California Legislative Information. California Code EVID 801 – Opinion Testimony by Expert Witness
Kelly/Frye and Sargon
When an expert relies on a new or novel scientific methodology, California applies the Kelly/Frye standard from People v. Kelly (1976), rooted in the earlier federal Frye decision. The methodology must be generally accepted within the relevant scientific community before testimony based on it is allowed.26Justia. People v. Kelly, 17 Cal. 3d 24 California has not adopted the federal Daubert standard, which gives judges broader discretion. Kelly/Frye remains the test for novel science in California state courts.
For expert testimony more broadly, the California Supreme Court’s 2012 decision in Sargon Enterprises, Inc. v. University of Southern California established that trial judges have an affirmative gatekeeping duty. 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.27Justia. Sargon Enters., Inc. v. Univ. of S. Cal. Before Sargon, many California courts were reluctant to exclude expert testimony and treated flawed logic as something cross-examination would expose. Sargon made clear that judges cannot simply pass questionable opinions to the jury.
Experts and Hearsay After People v. Sanchez
A 2016 California Supreme Court decision changed how experts can use out-of-court information. In People v. Sanchez, the court held that when an expert relates case-specific facts from hearsay sources and treats those facts as true to support an opinion, those statements are hearsay and must be independently proven or fall within a recognized exception.28Justia. People v. Sanchez – 2016 California Case Law Before Sanchez, experts routinely testified about the contents of police reports, lab results, and other records they didn’t personally create, treating those contents as established. That practice is now significantly constrained. If the hearsay statements are also “testimonial,” meaning made primarily for use in prosecution, admitting them without the declarant available for cross-examination violates the Confrontation Clause as well.
Authentication and Digital Evidence
Before any document, photograph, or recording comes in, the party offering it must authenticate it, meaning prove it is what they claim. 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 methods the law allows.29California Legislative Information. California Code EVID 1400 – Authentication of a Writing Evidence Code 1401 makes authentication a prerequisite. No writing comes in without it.30California Legislative Information. California Code Evidence Code 1401 – Requirement of Authentication
For contracts, authentication might be a witness confirming the signature. For photographs, a witness at the scene can testify the image accurately depicts what they saw. For digital evidence (emails, text messages, social media posts), authentication is harder. Courts look at identifying characteristics like email addresses, phone numbers, timestamps, and metadata. Testimony from the sender or recipient often provides the foundation, but when 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.31FindLaw. People v. Beckley In criminal cases, chain-of-custody documentation for digital evidence is critical to defeating claims of tampering.
Judicial Notice
Not everything needs to be proven through testimony and exhibits. Under Evidence Code 452, courts can take judicial notice of certain facts that are either commonly known in the community or easily verified through reliable sources, such as the day of the week a particular date fell on, or a published government interest rate.32California 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 requesting judicial notice of less obvious facts typically needs to give the court enough information to verify the fact from an indisputably accurate source.