What institutional arrangements for an independent central bank with a price stability mandate promote good policy outcomes when unconventional policies become necessary? Unconventional monetary policy poses challenges. The large scale asset purchases needed to counteract the zero lower bound on nominal interest rates have uncomfortable fiscal and distributional consequences and require central banks to assume greater risks on their balance sheets. Lack of clarity on the precise definition of price stability, coupled with concerns about the legitimacy of large balance sheet expansions, hinders policy: It encourages the central bank to eschew the decisive quantitative easing needed to reflate the economy and instead to accommodate too-low inflation. The experience of the Bank of Japan's encounter with the zero lower bound suggests important benefits from a clear definition of price stability as a symmetric 2% goal for inflation, which the Bank of Japan adopted in 2013.
Keywords: Bank of Japan; Zero lower bound; Quantitative easing; Central bank independence; Price stability; Inflation target; Balance sheet risk
Views expressed in the paper are those of the authors and do not necessarily reflect those of the Bank of Japan or Institute for Monetary and Economic Studies.