Of course, any such support policy, if anticipated, will be taken into account when banks establish their risk management frameworks for “tail” events. Still, one cannot generally conclude from this that central banks should not re-act and support the system in the case of severe tensions. To rigorously analyse moral hazard issues relating to financial crisis management by central banks, one first needs to distinguish between different but interrelated types of policy interventions. The reason for this is that the possible effects on incentives of different measures can be very diverse. However, this differentiation has often been missed when criticising central bank actions on the grounds of moral hazard considerations. 3  A. Giovannini and L. Spaventa (2007), “Subprime lessons: fix the information gap”, 5 November 2007, http://www.voxeu.org/index.php?q=node/690. BIS Review 143/2007  5  Let me distinguish briefly between four possible types of central bank measures: First, moral hazard issues have been raised in relation to the case in which the central bank lowers its key policy rate in response to financial turmoil. It has been argued that, if central banks lower interest rates at a time of market corrections and declining asset prices, economic agents may believe that the policy-makers are prepared to use monetary policy to support asset price valuations in order to prevent market downturns. If such belief becomes widespread, investors are likely to engage in excessive risk-taking behaviour, thereby sowing the seeds of future financial crises.
Events like this conference can prove of great help for the purpose of defining more precisely those gaps and to show the way forward. Thanks very much for your attention. 8  BIS Review 143/2007