Mason was the representative for Illinois’s 21st congressional district and was a Democrat. He served from 1935 to 1936.
The information on this page is originally sourced from a variety of materials, including:
- unitedstates/congress-legislators, a community project gathering congressional information
- United States Congressional Roll Call Voting Records, 1789-1990 by Howard L. Rosenthal and Keith T. Poole.
- Martis’s “The Historical Atlas of Political Parties in the United States Congress”, via Keith Poole’s roll call votes data set, for political party affiliation for Members of Congress from 1789 through about year 2000