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San Luis Obispo County, California

 > County of San Luis Obispo > District Attorney > Bureau of Investigations

Bureau of Investigations


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William Hanley
Chief Investigator


Mark Vallely
Asst. Chief Investigator

Terry O'Farrell
Asst. Chief Investigator


The San Luis Obispo County District Attorney’s Bureau of Investigation is staffed by over 15 sworn peace officers.  A District Attorney Investigator hired by the San Luis Obispo District Attorney’s Office has an average of 15 years law enforcement experience.  Typically, our Investigators have served with a police or sheriff’s department a minimum of five years as a detective before transitioning to a position as a District Attorney Investigator.


The primary function of the Bureau of Investigations is to provide quality and timely investigative support for the prosecutorial functions of the Office of the District Attorney.  Investigators collaborate with Deputy District Attorneys in the vigorous enforcement of criminal and civil laws.


Assisting other law enforcement agencies, when requested, is also an important function of the Bureau of Investigations, when additional manpower or expertise is needed.


Specialty units within the Bureau of Investigations work directly with Deputy District Attorneys in the office’s specialized programs to investigate:

  • Homicides
  • Gangs
  • Domestic Violence
  • Sexual Assault
  • Elder Abuse
  • Major Financial Crimes
  • Parental Abductions
  • Narcotics

The District Attorney’s Office’s Bureau of Investigations is committed to serve and protect the greater public interest through the fair and impartial administration of justice.