The office was renamed the King County Department of Public Safety after voters approved a charter change in 1968, and the director would be appointed.

The KCSO Motor Unit existed under contract with the King County Department of Transportation: Roads Division, which in turn provided funding for S.T.E.P (the Selective Traffic Enforcement Program) which targeted select arterials within unincorporated King County based on a history of accidents, chronic traffic problems, and high citizen complaints.

The Motor Unit participated in traffic enforcement, instructor certifications, dignitary protection and escort, parades and special events, educational and school activities as well as extensive motorcycle training.

The King County Sheriff's Office has a volunteer program for individuals between the ages of 14 and 21 who are interested in investigating a career in the field of law enforcement.

Officers responding to the shooting allegedly[citation needed] failed to gather evidence, moved items at the crime scene and acted as advocates for the shooters.

[21] In 2017 Detective Richard Rowe in plain clothes approached a motorcyclist from behind with his gun drawn without identifying himself as a law enforcement officer for a full minute.

[22] In March 2021, the King County Sheriff's Office agreed to pay out a $5 million settlement to the family of Tommy Le, a 20-year-old high school student who was shot and killed by Deputy Cesar Molina in 2017.

An investigation by the sheriff's office Use of Force Board cleared the shooting on the basis that deputies "reasonably believed that [Le] was armed with a deadly weapon and had already attacked someone with a knife".

[23] However, a subsequent outside review of the case found a "lack of rigor" in the sheriff's office's investigation, pointing to significant issues such as evidence suggesting that Le was likely moving away from the deputies when he was shot.