Washington State Investigators

Seattle Private Investigator | Private Investigation Services in Washington State

Washington State Investigators provides licensed, fully insured private investigation services based in greater south Seattle (Burien), serving clients throughout King, Pierce, and Snohomish counties, as well as statewide across Washington. We specialize in professional surveillance, legal evidence development, and thorough background investigations for attorneys, businesses, and private clients. For discreet, evidence-driven investigative services, call (206) 661-0412, SMS (425) 835-3860 or email info@wsipi.com for more information.

Professional private investigator providing legal evidence and litigation support for attorneys in Seattle and King County.

Attorneys

Attorneys often face “information gaps” that can stall a case. Our investigative services provide the missing pieces through strategic litigation support and precise evidence collection. From Seattle and King County to statewide WA, we help law firms leverage their position by uncovering facts that shift the legal advantage. Don’t just argue your case, prove it with professional insights designed specifically for Washington State attorneys.

Washington State civil investigator conducting surveillance and gathering evidence for civil trials and domestic cases.

Civil Investigations

Civil investigations are about more than just data; they are about protecting your rights and assets. Whether it involves domestic surveillance, complex background checks, or locating hidden wealth, our civil investigators assemble the truth needed for trial. We specialize in uncovering the “hidden” details of civil cases in Washington, providing you with the clarity and court-ready proof required to win your dispute.
Criminal investigator in Seattle researching case files and locating evidence for criminal defense cases.

Criminal Investigations

Criminal investigations require a relentless pursuit of the facts to ensure a fair defense. Our team specializes in criminal defense investigation, focusing on witness interviews and evidence re-evaluation that others often overlook. Serving Seattle and King County, we dig deep into case files to find flaws in the prosecution’s narrative, giving you the professional investigative support necessary to protect your client’s future.

Why Choose Washington State Investigators?

WSI PI News 

Small Business Excellence Award - Washington State Investigators 2020 Small Business Excellence Award
  • Licensed in WA | Active credential
  • Fully Insured in WA | Active COL
  • 17+ Years Investigative Experience
  • AAS | Networking & Security
  • Background | OSINT | Research
  • Civil | Criminal Investigations
  • Covert Surveillance Specialists
  • Crypto | Cyber Investigations
  • Personal Injury Litigation Support
  • Property Loss Prevention
  • Specialty Databases | Resources
  • Serving Seattle | Washington State
  • Confidentiality | Integrity | Professionalism

About Washington State Investigators

Principal Investigator

Wolfgang Grasst, founder of Washington State Investigators, merges IT Networking & Security with professional field tradecraft. Based in Seattle, he delivers high-level intelligence and surveillance services for complex cases statewide. He focuses on uncovering facts through a blend of technical precision and traditional investigative experience.

As a Navy Veteran and digital discovery specialist, Wolfgang ensures that every case, from domestic surveillance to witness locates, is handled with total discretion and provides the court-ready proof required to move forward with confidence.

Read Wolfgang’s Full Bio →

Research & Surveillance

We specialize in uncovering what others miss. From infidelity surveillance and hidden asset searches to professional person locates, our agency focuses on high-level intelligence for complex legal matters. We utilize advanced OSINT and covert field operations to provide proof for civil and criminal investigations.

We bridge the gap between traditional field surveillance and modern digital intelligence, ensuring a comprehensive view of the facts. Our goal is to provide actionable data and photographic evidence that stands up under the scrutiny of the legal system.

View All Specialized Services →

Investigative Resources

Empower your research with our Free PI Resources Center. We provide access to vital tools for public records, background checks, including state & federal resources, and investigative guides designed for your use. By sharing our expertise, we ensure you have the best investigative tools and resources to begin your research.

Explore our list of databases and state-specific search tools to gain the insight you need before proceeding with your research. We know access to reliable information is your most valuable asset in a legal dispute, domestic matter, or criminal case.

Access Free Tools & Databases →

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Washington State Investigators

Washington State Investigators 17 Yrs Investigative Experience Licensed and Fully Insured Private Investigator Lic #4287
Mailing Address:
1016 SW 150th St #3 Burien | Seattle, WA 98166
Service Area:
Burien, Seattle, King, Pierce, & Snohomish Counties
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