Giessel represents District N in the Alaska Senate, including Northeast Anchorage, Anchorage Hillside and the Turnagain Arm communities of Bird, Girdwood, Indian, and Anchorage, all within the Municipality of Anchorage.
First elected in 2010 while identifying with Tea Party values, she has also served as the vice-chair of the state Republican Party and had a career in nursing.
Following redistricting, she was elected to a different senate seat in 2012.
Giessel serves as chair of the Resources Committee and is a member of the Senate Majority Caucus.
After Senate President Pete Kelly was unseated in 2018, Giessel was elected president of the Alaska Senate.