Tom Andersen graduated from the University of Oregon School of Law in 1976 and established himself as a partner and litigator in a Eugene-based firm, specializing in civil and criminal trials. Transitioning to public service in 1986, he worked as a trial lawyer for the State Accident Insurance Fund Corporation. Andersen opened his own practice in 2007, concentrating on workers' compensation cases. His career in public service continued with his election to the Salem City Council in 2014, where he served two terms and focused on economic, environmental, and social justice initiatives. Andersen was elected to the Oregon House of Representatives for the 19th district in 2023.

Tom Andersen blends a progressive approach to social justice with an unexpectedly conservative stance on economic regulation. His legislative record reveals a calculated effort to balance environmental advocacy with the protection of local industries. Andersen's rhetoric often emphasizes community resilience and inclusivity, yet he simultaneously champions policies that streamline business operations. This juxtaposition invites scrutiny into how he reconciles these seemingly divergent priorities. Andersen's leadership on racial justice issues further complicates his ideological profile, suggesting a deeply rooted commitment to equity that transcends traditional political boundaries.