The Washington Rules of Evidence, cited as the “ER” rules, decide what a judge or jury is allowed to hear in a civil or criminal trial in state court. The baseline is permissive: relevant evidence comes in unless a specific rule, statute, or constitutional provision keeps it out. Most of the work happens in those exceptions, and in several of them Washington parts company with federal practice. What follows is a working map of how admissibility is decided, what the main exclusions are, and where the state goes its own way.
Relevance Is the Threshold
Every exhibit and every answer has to clear ER 401 first. Evidence is relevant if it makes any fact that matters to the case more or less likely than it would be without the evidence. The bar is deliberately low. ER 402 then supplies the default rule: relevant evidence is admissible unless the state constitution, a statute, or the evidence rules themselves say otherwise, and irrelevant evidence is never admissible.1Washington State Courts. Washington Rules of Evidence – ER 402
Clearing relevance is not the end. Under ER 403, a judge may exclude relevant evidence if its value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, misleading the jury, undue delay, wasted time, or needless repetition.2Washington Courts. Washington Rules of Evidence – ER 403 Exclusion of Relevant Evidence on Grounds of Prejudice, Confusion, or Waste of Time The word to focus on is “substantially.” The risks have to clearly outweigh the probative value, not merely match it. A graphic injury photograph might be relevant to damages and still be excluded because its shock value drowns out what it actually proves. This is the balancing test judges apply most often, and it sits in the background of nearly every other admissibility fight.
Character Evidence and Prior Bad Acts
ER 404 blocks one of the most intuitive arguments people want to make at trial: that someone acted a certain way this time because they have a history of acting that way. Evidence of a person’s character trait is not admissible to prove they acted in conformity with it on a specific occasion.3Washington State Courts. Washington Rules of Evidence – ER 404 Character Evidence Not Admissible to Prove Conduct; Exceptions; Other Crimes
Criminal cases have narrow exceptions. A defendant can introduce a relevant character trait, such as a reputation for peacefulness in an assault case, and the prosecution can rebut it. In homicide cases, the prosecution can offer evidence that the victim was peaceful to counter a claim that the victim struck first.
The provision that produces the most courtroom argument is ER 404(b), which deals with other crimes, wrongs, or acts. Those cannot come in to show the person is the type who would commit this offense. They can come in for other specific purposes: motive, opportunity, intent, preparation, plan, knowledge, identity, or absence of mistake. Even when the purpose qualifies, the judge still runs the evidence through the ER 403 balance before admitting it.
Hearsay and Its Exceptions
Hearsay is a statement made outside court that a party offers at trial to prove the statement is true. ER 801 defines it; ER 802 bars it by default.4Washington State Courts. Washington Rules of Evidence – ER 801 The reason is practical. The person who made the statement is not on the witness stand, so no one can cross-examine them about whether they were lying, mistaken, or misunderstood.
ER 803 then creates a long list of exceptions that apply whether or not the person who made the statement is available to testify. The most commonly used:
- Excited utterances under ER 803(a)(2): a statement about a startling event made while the speaker was still under the stress of the excitement.
- Present sense impressions under ER 803(a)(1): a statement describing an event made while the speaker was perceiving it or immediately afterward.
- Statements for medical diagnosis or treatment under ER 803(a)(4): a patient’s description of symptoms, history, or general cause of injury given to get medical care.
- Business records under ER 803(a)(6): records kept in the regular course of a business activity, made at or near the time of the event by someone with knowledge, where making such records was a routine practice.
Each exception rests on circumstances that give the statement enough built-in reliability to compensate for the missing cross-examination.5Washington State Courts. Washington Rules of Evidence – ER 803 Hearsay Exceptions ER 804 adds more exceptions that only apply when the person who made the statement is unavailable, including former testimony given under oath at a prior proceeding and statements made by someone who believed death was imminent.
Evidence Excluded for Policy Reasons
Some reliable evidence is still kept out because admitting it would discourage behavior the system wants to encourage.
ER 407 covers subsequent remedial measures. If someone takes steps after an accident that would have made the accident less likely, the fix cannot be used to prove they were negligent or at fault. If repairing a broken staircase after a fall could be held against you in court, the incentive would be to leave it broken. The rule still allows evidence of the repair for other purposes, such as proving ownership, control, or that a safer design was feasible.6Washington State Courts. Washington Rules of Evidence – ER 407 Subsequent Remedial Measures
ER 408 keeps settlement discussions out. In a civil case, evidence that someone offered or accepted a settlement, and statements made during those negotiations, are not admissible to prove liability or the value of a disputed claim. Evidence that was independently discoverable does not become privileged just because it surfaced during settlement talks, and settlement evidence can still be used for limited purposes like showing a witness’s bias.7Washington State Courts. Washington Rules of Evidence – ER 408 Compromise and Offers to Compromise
ER 410 does the same work in criminal cases. A withdrawn guilty plea, a no-contest plea, or statements made during plea discussions cannot be used against the person who made them in any later civil or criminal proceeding. The one carve-out: statements made under oath and with counsel present can be used in a prosecution for perjury.8Washington State Courts. Washington Rules of Evidence – ER 410 Inadmissibility of Pleas, Offers of Pleas, and Related Statements
Witnesses: Who Can Testify and How Credibility Is Attacked
Washington presumes competency broadly. ER 601 treats every person as competent to testify unless a statute or court rule says otherwise, so there is no automatic disqualification based on age or mental capacity.9Washington State Courts. Washington Rules of Evidence – ER 601 General Rule of Competency ER 602 then requires personal knowledge: a witness has to have actually perceived the matters they describe.
Once a witness testifies, any party, including the one that called them, may attack credibility. ER 607 establishes that open-door policy.10Washington Courts. Washington Rules of Evidence ER 607 – Who May Impeach Common methods include showing a prior inconsistent statement, demonstrating bias, or attacking character for truthfulness under ER 608.
Impeachment With Prior Convictions
ER 609 controls when a witness’s criminal record can be used against their credibility. Two categories qualify. Any crime punishable by more than one year in prison can be used if the court decides the evidence’s value outweighs the prejudice to the party it hurts. Any crime involving dishonesty or false statement, such as fraud, forgery, or perjury, comes in regardless of the potential sentence, with no balancing required.11Washington State Courts. Washington Rules of Evidence – ER 609 Impeachment by Evidence of Conviction of Crime
There is a time limit. Convictions older than ten years, measured from the conviction date or release from confinement, whichever is later, are presumptively excluded. A court can still allow them, but only if specific facts show the value substantially outweighs the prejudicial effect, and the party seeking to use the conviction gave advance written notice.
Opinion Testimony and the Frye Standard for Experts
ER 701 lets lay witnesses offer opinions grounded in their own perception when those opinions would help the jury understand the facts. A bystander can testify that a driver appeared intoxicated or that a car looked like it was going about 50 miles per hour.12Washington Courts. Washington Rules of Evidence – ER 701 Opinion Testimony By Lay Witnesses Opinions that require specialized knowledge belong to experts.
Expert testimony under ER 702 is allowed from a witness qualified by knowledge, skill, experience, training, or education when it would help the jury understand the evidence or resolve a factual dispute.13Washington State Courts. Washington Rules of Evidence – ER 702 Testimony by Experts Here is where Washington diverges from federal practice. Federal courts and most states use the Daubert standard, which gives trial judges broad discretion to evaluate whether an expert’s methods are reliable. Washington rejected Daubert and follows the older Frye general acceptance test. Novel scientific evidence is admissible only if the methodology has gained general acceptance in the relevant scientific community. The Washington Supreme Court has reaffirmed this position multiple times and has held that ER 702 does not incorporate the Daubert reliability framework. The practical consequence shows up with cutting-edge forensic techniques: an expert opinion that would pass in federal court can be excluded in a Washington courtroom when the underlying method has not been broadly accepted.
Privileges Come From Statute, Not the ER Rules
ER 501 does not create any privileges on its own. It points to a list of state statutes that establish specific privileges and confidential communication protections, so the actual rules sit in the Revised Code of Washington.14Washington State Courts. Washington Rules of Evidence 501
The attorney-client privilege is established in RCW 5.60.060. An attorney cannot be examined about any communication a client made to them, or any advice given in return, during the course of professional employment, unless the client consents. Washington extends the shield further than many states: a parent or guardian present during communications between a minor child arrested on criminal charges and the child’s attorney is also protected from being compelled to testify about those communications.15Washington State Legislature. RCW 5.60.060
Other statutory privileges in Washington cover the physician-patient relationship, spousal communications, and clergy-penitent communications, among others. The privilege belongs to the person who shared the confidential information, and only that person or their representative can waive it. Voluntary disclosure to a third party outside the protected relationship generally destroys the privilege.
Authentication, Including Emails and Social Media
Before a document, object, or recording is admitted, the party offering it has to show it is what they claim. ER 901(a) sets a lower bar than people often expect: enough evidence to support a finding that the item is genuine, not proof beyond a reasonable doubt.16Washington Courts. Washington Rules of Evidence ER 901 – Requirement of Authentication or Identification The most common method is testimony from a witness with personal knowledge: someone who recognizes the handwriting, was present when a photo was taken, or can identify an object from the scene. ER 901(b) lists additional methods, including distinctive characteristics of the item, voice identification, and comparison with authenticated samples.
Washington has written for electronic evidence more explicitly than many states. ER 901(b)(10) addresses email directly. A person with knowledge can authenticate an email by testifying that it appears to come from a particular sender, was sent from an address associated with that sender, and that its appearance, contents, and other characteristics support a finding that it is what it claims to be.
Text messages and social media posts do not have their own subsection. Courts handle them through the general standard in ER 901(a) and the “distinctive characteristics” provision in ER 901(b)(4). Content, writing style, references to known facts, and contextual details can all support authenticity. A bare screenshot without metadata showing when and how it was captured is easier to challenge, because web content is simple to manipulate. A stronger chain, with timestamps, URLs, and testimony from the account owner, improves the odds of admission.
How to Preserve an Evidence Ruling for Appeal
Knowing the rules does little good if the record is not built correctly during trial. ER 103 governs how evidentiary errors are preserved, and skipping its steps can forfeit the right to challenge a ruling on appeal.17Washington State Courts. Washington Rules of Evidence – ER 103 Rulings on Evidence
When the court admits evidence you believe should be excluded, you must make a timely objection or motion to strike and state the specific ground. A general “I object” without more will not preserve the issue. When the court excludes evidence you want admitted, you must make an offer of proof describing what the evidence would have shown, unless the substance was already clear from the questions being asked.
In jury trials, objections and offers of proof should take place outside the jury’s hearing whenever possible. The point of excluding evidence is defeated if the jury hears a detailed description of it during the argument over whether to admit it.