Judge Spearman obtained her Bachelor of Arts degree in Psychology from Rutgers University in 1981. In 1984, she received her Juris Doctor degree from the University of Washington.

Following her admission to practice in 1985, Judge Spearman served as Staff Attorney for the Defender Association in Seattle, where she was assigned to felony juvenile and misdemeanor divisions. During her seven years in this capacity, she tried over 75 felony and 30 misdemeanor cases to verdict.

Upon leaving the Defender Association, Judge Spearman focused for a time on family law and criminal matters through her own law offices. Beginning in 1993, she acted as Judge Pro Tem, presiding over cases in King County Superior Court, Seattle District Court and Seattle Municipal Court.

Since Judge Spearman's appointment to the Kirkland Municipal Court in 1994, she has established all court programs and procedures, created the Student Traffic Court Program, established the Mentor Program matching youth in need with community volunteers, organized the day/home detention programs which offer an alternative to jail, and effective January 2000, will be hearing cases from the cities Medina, Hunts Point, Yarrow Point, and Clyde Hill.

Judge Mariane Chi Spearman believes in participation in both professional and community activities. She recently served as a Panelist in the Judicial College Judicial Independence Forum and as Co-President of the Lowell PALS PTA. In the past, her activities have included acting as Coordinator for the Asian Bar Association Community Law Program, teaching Criminal Law at Highline Community College, and volunteering at the Korean Bar Association Counseling Center. Judge Spearman has also served as Judge of the King County Kids Court since 1994.