Masyumi Party
Roem was a senior figure in the Masyumi Party, which was banned by President Sukarno in 1960 for its support of the PRRI rebellion. In 1962 he was arrested and jailed without trial in Madiun, together with Sutan Sjahrir, Anuk Agung, the sultan of Pontianak Hamid and Soedarpo Sastrosatomo. They were released by attorney-general Sugi Aito in May 1966.