Tom O'Halleran served as the U.S. Representative for Arizona's 1st Congressional District from 2017 to 2023. During their time in Congress, O'Halleran was assigned to the House Committees on Agriculture from 2017-2022 and Energy and Commerce from 2019-2022. They developed water policies for Arizona and other Western states and supported legislation that invested in education, veteran services, tribal communities, and health care.