[1] Following graduation from Kalani High School,[3] he graduated with a degree in history from Pennsylvania State University, and upon returning to Hawaii, began working for his family's real estate company.

[4][5] He defeated incumbent Tom Brower in the Democratic Party primary election,[3][6] then won the general election for the 22nd district of the Hawaii House of Representatives against Republican Party candidate Nicholas Ochs, who previously served as the vice chairman of Donald Trump's Hawaii campaign in the 2016 United States elections, had strong support from Roger Stone and drew media attention for founding the Hawaii chapter of the Proud Boys.

[7][8][9][10][11] After Tam was seated, he became the only openly gay member of the Hawaii State Legislature.

[12][13][a] Following the 2021 storming of the United States Capitol, Tam and other Hawaii lawmakers signed a letter requesting rioters to be placed on the federal No Fly List.

[20] In December 2023, Tam was elected interim Chair of the Democratic Party of Hawaii by the State Central Committee.