After graduating from secondary school in 1968, Bartels was admitted to the University of Ghana, where he studied law. After obtaining his bachelor's degree in 1971, Bartels continued his studies at the Ghana School of Law in order to become a professional lawyer.
In 1979, Bartels first contested for a seat in the Parliament of Ghana, but was defeated by a People's National Party candidate. In 1992, Bartels again stood for election in Agona West constituency, but withdrew after his party boycotted the 1992 election due to alleged electoral fraud. In 1996, Bartels was elected MP for the Ablekuma North constituency. He was the Minister for Works and Housing from 2001 -2004. He subsequently became Minister in charge of Private Sector and PSI (2005-2006), Minister of Information & National Orientation (2006-2007), and Minister of the Interior (2007-2008).
Bartels was fired from the cabinet by President John Kufuor in 2008, allegedly due to his involvement in the missing of forty-two parcels of cocaine which were confiscated by the police, Bartels denied his involvement in that. A lot of senior NPP members said he was sacked because of his support for his close friend the then Candidate Nana Addo Dankwa Akufo-Addo, they claim the then president Kufour wanted Bartels to use his influence in the Central Region to garner votes for Alan Kyeremanteng. Bartels was said to be rooting for Akufo Addo in the Central Region. It is also alleged that Bartels channeled considerable amounts of a US-sponsored government fund meant for the Ghanaian private sector to companies owned by his daughters and sons-in-law.
Bartels is a member of the Afro-European Bartels family, whose ancestor Cornelius Ludewich Bartels was Governor-General of the Dutch Gold Coast between 1798 and 1804, and whose son Carel Hendrik Bartels was the most important mulatto trader on the Gold Coast in the second quarter of the nineteenth century.