During his tenure as Minister of Culture, he worked on integrating cultural initiatives into daily life, emphasizing education, audiovisual development, and urban aesthetics. He also implemented reforms to support decentralized cultural organizations and promoted art in public buildings.
In addition to his ministerial roles, Duhamel was a Member of Parliament representing Jura and the mayor of Dole. Despite battling a long illness, he remained active in public life until his death in 1977 at the age of 52.