Understanding Motions to Suppress Evidence in Washington Criminal Cases

When a person faces criminal charges, the strength of the government’s case often depends on the admissibility of the evidence. However, not all evidence is obtained lawfully. If law enforcement violates a defendant’s constitutional or statutory rights, that evidence may be excluded through a motion to suppress.

What Is a Motion to Suppress?

A motion to suppress is a formal request asking the court to exclude evidence from trial because it was gathered in violation of the law. If the motion is granted, the prosecution cannot use that evidence to prove its case. In many instances, suppression can significantly weaken the government’s position, sometimes resulting in dismissal or reduction of the charges.

Common Grounds for Suppression

Several legal theories may support a motion to suppress. The most frequently litigated include:

1. Unlawful Search or Seizure

The Fourth Amendment to the U.S. Constitution and Article I, Section 7 of the Washington Constitution protect individuals from unreasonable searches and seizures. Evidence may be suppressed if:

  • Law enforcement conducted a search without a warrant and no valid exception applied (such as consent, exigent circumstances, or probable cause).
  • The search exceeded the scope of the warrant.
  • The initial stop or detention was not supported by reasonable suspicion or probable cause.

Example:
If officers stop a vehicle without any legal justification and discover contraband, the evidence may be subject to suppression.

2. Violation of Miranda Rights

Before engaging in custodial interrogation, police are required to advise a suspect of their rights, including the right to remain silent and the right to an attorney. Failure to provide Miranda warnings can result in the exclusion of any statements obtained during questioning and any evidence derived from those statements.

3. Involuntary Statements

Even when Miranda warnings are given, a confession must be voluntary to be admissible. Coercive tactics, threats, or promises of leniency can render statements involuntary, warranting suppression.

4. Arrest Without Probable Cause

If law enforcement arrests an individual without probable cause, evidence seized as a result—such as through a search incident to arrest—may be inadmissible.

5. Defects in the Chain of Custody

Evidence must be properly handled, documented, and preserved. Substantial gaps in the chain of custody can raise questions about authenticity or contamination, potentially leading to suppression.

The Suppression Hearing

Once a motion to suppress is filed, the court will schedule a suppression hearing, known as a CrR 3.6 hearing in Washington Superior Courts.

At this hearing:

  • The prosecution bears the burden of demonstrating that the evidence was lawfully obtained.
  • Defense counsel may cross-examine the officers and present supporting evidence.
  • The judge will evaluate the facts and determine whether the evidence should be excluded.

Suppression hearings are often pivotal proceedings that can shape the outcome of a case.

Why Suppression Motions Are Important

Motions to suppress play a critical role in protecting constitutional rights and maintaining the integrity of the criminal justice system. Successfully excluding unlawfully obtained evidence can:

  • Substantially weaken or eliminate the prosecution’s case,
  • Provide leverage in plea negotiations, or
  • Result in dismissal of the charges altogether.

Given the complexity of these issues, it is essential to work with a defense attorney experienced in constitutional law and suppression litigation.

Speak with a Criminal Defense Attorney

If you are facing criminal charges in Washington, it is important to understand your rights and options. The Law Office of Erin Bradley McAleer has extensive experience litigating suppression motions and defending clients against criminal allegations.

To discuss your case in a confidential consultation, contact our office today.