He served in the Maryland House of Delegates as a Democrat from the 45th district from 1971 to 1995 during which time he resided in Baltimore.
[7] After retiring from the Maryland House of Delegates, Douglass worked as the Deputy Director for the State Department of Assessments and Taxation.
[8] In 1985, Douglass voted to kill a proposal made by Governor Harry Hughes that would ease the state's restrictions on the public funding of abortions.
[11] In 1987, Douglass applied become the next Maryland State Treasurer, but withdrew his candidacy after forming a coalition with Lucille Maurer, who agreed to appoint Douglass as her chief deputy treasurer in exchange for the Legislative Black Caucus of Maryland's votes.
[15] In November 2021, Douglass applied become the next Maryland State Treasurer following the retirement of Nancy Kopp on December 17, 2021.