In 2010 he was elected to the Washington State Senate representing Legislative District 38 in a controversial contest that led to the Moxie Media scandal.

[1] After his admission to the Washington State Bar, Harper worked for several law firms, and briefly served as governmental affairs director for the Snohomish County-Camano Island Association of Realtors.

The scandal involved a campaign by Harper's supporters to funnel $300,000 to a variety of shell PAC's that was used to covertly assist an unknown third-party candidate, helping eliminate Berkey from advancing to the general election.

[8] Harper joined the Master Builders Association of King and Snohomish Counties as its director of governmental affairs in the summer of 2016.

[8] In December 2017, Harper was designated deputy mayor of Everett, Washington by Mayor-Elect Cassie Franklin, and assumed office in 2018.