He served as Minister of Justice in 1848 - 1849 and then Minister of the Interior from 1849 to 1859. As a well-known Liberal lawyer, he was first called a "minister of barricades". However, he gradually accepted Conservative views.
After the death of Felix, Prince Schwarzenberg in 1852, he largely dictated policy in Austria and Hungary. Bach centralised administrative authority for the Austrian Empire, but he also endorsed reactionary policies that reduced freedom of the press and abandoned public trials. He represented later the Absolutist (or Klerikalabsolutist) direction, which culminated in the concordat of August 1855 that gave the Roman Catholic Church control over education and family life.
Bach was created Baron (Freiherr) in 1854. He was also the guardian of Science Academy (Akademie der Wissenschaften) in 1849 - 1859.
The pillars of so-called Bach system (Bachsches System) were, in the words of Adolf Fischhof, four "armies": a standing army of soldiers, a sitting army of office holders, a kneeling army of priests and a fawning army of sneaks.