An endogenous growth model with financial intermediation is used to show how government policies towards the financial sector can lead to banking crises and persistent growth slumps. The model shows how government deposit guarantees and regulatory forbearance can lead to permanent declines in the growth rate of the economy. The effects of inadequate prudential supervision on asset price dynamics under perfect foresight are also derived in the model. The policies that are used in the analysis are based on essential features of Japanese financial regulation. The implications of the model are compared to the experience of the Japanese economy and financial system during the 1990s. We find that the dynamics predicted by our model are generally consistent with the recent behavior of economic aggregates, asset prices and the banking system for Japan. A policy implication of the model is that the impact on future economic growth depends upon the length of time the government fails to enforce loan-loss reserving by banks.