In this connection, there is an argument that "independence on monetary policy granted to a central bank is operational independence and its objective should be decided by the government." In such an argument, an inflation target appears to be assumed as the objective that should be decided by the government.
Looking at central banks overseas, however, the objectives of monetary policy are clearly  BIS Review 87/2001  7  stipulated by law; no central bank decides its objectives by itself. The Bank of Japan is no exception and the Bank of Japan Law sets its objective as "contributing to the sound development of the national economy through the pursuit of price stability."