Michael Kwasi Ossei stood as a candidate for the National Liberation Movement, and were nicknamed "Domo" (Demo) by Dr Kwame Nkrumah"s CPP majority.
However, After Ghana attained its independence on 6 March 1957, the Parliament of Ghana passed the Avoidance of Discrimination Act, 1957 (C.A. 38), which banned all parties and organizations that were confined to or identifiable to any racial, ethnic or religious groups with effect form 31 December 1957
This law meant that all the existing political parties would become illegal. These parties included the Northern People's Party, Muslim Association Party, National Liberation Movement (NLM), Anlo Youth Organization, Togoland Congress and the Ga Shifimokpee.[2]
Due to his position in the NLM Ossei was detained together with other opposition candidates and sent to Nsawam prison for several months.
Once Nkrumah was deposed in a Coup d'etat in 1966, Michael Kwasi Ossei was appointed Chairman of The Koforidua Municipal Council. The NLM reorganised and now called itself Progress Party, (PP.). Ossei again stood as candidate for the PP and won. Becoming the MP for Koforidua constituency. In 1969, the PP won the parliamentary elections with 105 of the 140 seats. To form the government of Ghana. He was appointed Deputy Minister for Information, then later for the combined ministries of Works and Housing. A position he held until 1972 when the PP and Busia government were overthrown in a military coup by Colonel Ignatius Kutu Acheampong
Michael Kwasi Ossei began his political career in 1969 when he became the parliamentary candidate for the Progress Party (PP) to represent the Koforidua constituency prior to the commencement of the 1969 Ghanaian parliamentary election. He assumed office as a member of the first parliament of the second Republic of Ghana on 1 October 1969 after being a pronounced winner at the 1969 Ghanaian parliamentary election. His tenure ended on 13 January 1972.[3][4]