When you think about a courtroom trial, what comes to mind? For most people, it’s the drama of lawyers arguing before a judge and jury. But underneath that drama lies the real foundation of every case: evidence.
Whether you’re involved in a civil lawsuit like a personal injury claim, a criminal case, or even a family law dispute, evidence is what determines the outcome. Judges and juries don’t decide based on hunches or feelings—they decide based on the facts they are allowed to see and hear under the rules of evidence.
What Is Evidence?
Evidence is any information presented to prove or disprove a fact in a legal proceeding. It can be physical objects, documents, witness testimony, photos, videos, or even digital records like emails and text messages.
The core purpose of evidence is to help the judge or jury answer the essential questions of a case:
- What actually happened?
- Who is responsible?
- How much harm was done?
Without evidence, there can be no fair decision.
Types of Evidence
Lawyers often categorize evidence in several key ways. Here are some of the most common types:
1. Testimonial Evidence
This is what witnesses say under oath in court. Witnesses may testify about what they saw, heard, or know from personal experience. Expert witnesses, such as doctors or accident reconstructionists, provide specialized opinions to help the court understand complex issues.
2. Documentary Evidence
These are written materials like contracts, medical records, business records, emails, and text messages. Documentary evidence is vital in proving what was agreed to or what actually occurred.
3. Physical Evidence
Also called “real evidence,” these are tangible objects. For example, a damaged vehicle part in a product liability case or a blood-stained shirt in a criminal trial.
4. Demonstrative Evidence
This type of evidence helps explain or illustrate testimony. Think of charts, diagrams, maps, or computer simulations. It’s not the object itself that’s disputed, but rather, it helps make complex facts clear.
5. Digital Evidence
With today’s technology, digital records like GPS data, social media posts, surveillance video, and electronic communications are playing an increasing role in both civil and criminal cases.
Rules of Evidence in Washington State
Every state has its own rules about what evidence is allowed in court. In Washington State, courts follow the Washington Rules of Evidence (ER). These rules are designed to ensure that trials are fair, efficient, and that juries only see reliable information.
Relevance is key. Under Washington’s rules (ER 401 and 402), evidence must be relevant to be admitted. Relevant evidence is anything that makes a fact of consequence more or less probable than it would be without the evidence.
But even relevant evidence can be excluded. For example, ER 403 allows judges to keep out evidence if its probative value is substantially outweighed by dangers like unfair prejudice, confusion, or wasting time.
Hearsay and Exceptions
One of the most misunderstood evidence rules is hearsay. Generally, hearsay is an out-of-court statement offered to prove the truth of what it says, and it is not admissible under Washington’s ER 802.
But there are many exceptions.
For example:
- Excited utterances
- Business records
- Statements against interest
- Dying declarations
These exceptions recognize that some out-of-court statements are still reliable enough to be used in court.
Laying the Foundation
Just because something exists doesn’t mean it can immediately be shown to a jury. Lawyers must lay a proper foundation—essentially, they have to show the court that the evidence is authentic, relevant, and admissible.
For example, to admit a photograph, a witness might testify:
- That they took the photo
- When and where they took it
- That it accurately depicts what they saw
Without this foundation, the photo could be excluded.
Authentication
ER 901 of the Washington Rules of Evidence requires that evidence be authenticated before it’s admitted. That means the party offering the evidence must show it’s what they claim it is.
Examples of authentication include:
- Witness testimony verifying a signature on a document
- Metadata showing when a digital file was created
- Chain of custody logs for physical evidence in criminal cases
Expert Witnesses
Many cases involve technical or scientific issues that a typical juror wouldn’t understand without help. That’s where expert witnesses come in.
Under Washington’s ER 702, an expert can testify if:
- Their scientific, technical, or specialized knowledge will help the jury understand the evidence or determine a fact
- They are qualified by knowledge, skill, experience, training, or education
For example, a medical expert may explain the severity of injuries in a personal injury case, or an accident reconstructionist may describe how a collision occurred.
Privileges and Exclusions
Even relevant, reliable evidence may be excluded for policy reasons.
Washington law protects certain communications, such as:
- Attorney-client privilege
- Doctor-patient privilege
- Spousal communications
These privileges encourage open, honest communication in important relationships. Evidence that violates these privileges can be excluded even if it’s highly relevant.
The Burden of Proof
In civil cases like personal injury lawsuits, the burden of proof is on the plaintiff, who must prove their case by a preponderance of the evidence. That means showing it’s more likely than not that their version of events is true.
In criminal cases, the burden is much higher: beyond a reasonable doubt. This protects defendants from wrongful convictions.
Pretrial Discovery
Evidence doesn’t just appear at trial. Much of the work happens in discovery, the formal process where both sides exchange information.
In Washington, civil discovery rules allow:
- Depositions (out-of-court sworn testimony)
- Interrogatories (written questions)
- Requests for production (documents and records)
- Requests for admission (forcing the other side to admit or deny specific facts)
Discovery ensures that both sides know the evidence before trial, reducing surprises and promoting fair settlements.
Why a Lawyer Matters
Navigating Washington’s complex rules of evidence isn’t easy.
A skilled attorney knows:
- What evidence to gather
- How to get it admitted
- How to challenge the other side’s evidence
- How to present it clearly to a jury
In short, evidence can make or break your case. Whether you’re facing a personal injury lawsuit, criminal charge, or family law dispute, working with an experienced lawyer is the best way to ensure your evidence is heard and your rights are protected.
Contact Darrell Cochran Personal Injury Lawyer for a Free Consultation
Evidence is the foundation of justice. In Washington State courts, strict rules ensure that only reliable, relevant, and fairly presented evidence reaches the jury. Understanding those rules—and knowing how to use them—is essential in any legal case.
If you are involved in a legal dispute or have further questions about the rules of evidence, contact Darrell Cochran Personal Injury Lawyer today at (253) 948-0250 for a free, no-obligation consultation.