Stephenson was first elected to the
Minnesota House of Representatives in
2018. He chaired the Commerce Committee, and also served on the Climate and Energy Committee and the Elections Committee. In 2025, he co-chaired the Ways and Means Committee. During the 2019 session, Stephenson successfully authored a bill to get rid of Minnesota's "marital rape exception". Before his bill passed, Minnesota law prevented prosecution of rape in certain circumstances when the victim was married to the rapist. With the bill's passage, rapists can be prosecuted regardless of whether they are married to the victim. Stephenson also successfully authored a provision to take the first steps towards building a new
Mississippi River crossing between
Dayton, Minnesota, and
Ramsey, Minnesota. In 2020, Stephenson was the chief author of a bill to provide grants to small businesses that were not able to operate due to the
COVID-19 pandemic. The bill allocated $62.5 million in grants up to $10,000, with $18 million reserved for microbusinesses, defined as businesses with less than 6 employees. Stephenson's bill passed the House by a margin of 129 to 5 and was unanimously approved in the Senate. Stephenson's legislative priorities include consumer protection and combating climate change. In 2021, he authored the Energy Conservation and Optimization Act, which significantly expands Minnesota's
energy conservation programs. The bill is expected to cut carbon emissions in Minnesota, in particular by incentivizing "fuel switching", whereby utilities offer consumers incentives to switch from less efficient fossil fuels to more efficient electricity. Stephenson also authored the Natural Gas Innovation Act (NGIA), which passed into law with bipartisan support in 2021. NGIA gives Minnesota regulators and utilities new tools to decarbonize the building sector, establishes a new goal to reduce the use of fossil gas, and starts a new regulatory proceeding to plan for further
decarbonization. In 2021, Stephenson also secured passage of Minnesota's Student Borrower's Bill of Rights, which regulates student loan servicers and protects student borrowers from abusive practices. He has also authored legislation to ban price gouging by prescription drug companies. Stephenson also authored legislation that banned political donations from foreign-owned corporations, a bill providing a rebate for electric vehicles, and legislation to criminalize certain misleading
deepfakes. ==Personal life==