Steve and his wife, Nicole, hail from Aberdeen, South Dakota. He is a graduate of Roncalli High School and received his undergraduate degree from the University of South Dakota. He later earned his Master's degree in Business Administration from the University of Sioux Falls. Steve has held positions within the South Dakota Republican Party, Wells Fargo, and United States Senator John Thune's office.
In 2018, the citizens of South Dakota elected Steve as Secretary of State. Secretary Barnett is a member of the National Association of Secretaries of State. Prior to being elected as Secretary of State, Steve served two terms as South Dakota State Auditor (2010 and 2014). As State Auditor, Steve was selected by his peers to serve as Vice-President of the National Association of State Comptrollers (NASC), as well as serving on the Executive Committee of the National Association of State Auditors, Comptrollers, and Treasurers (NASACT).
Steve's interest in public service was sparked at an early age by his grandfather, the late Joe Barnett, Sr. Joe served as Speaker of the House and Republican Majority Leader in the South Dakota House of Representatives during his 19 years in public office.
Steve and Nicole have four children; Emma, Henry, William and Lillian. Steve and his family are members of Saints Peter and Paul Parish in Pierre. He has been actively involved in numerous volunteer activities, including Junior Achievement of South Dakota, Knights of Columbus and the American Legion Boys State program. He also serves as a board member for the Oahe YMCA and the Catholic Community Foundation for Eastern South Dakota. In his free time, Steve enjoys spending time with his family, pheasant hunting, and snow and water skiing.