This paper offers a possible explanation for the conflicting results in the literature concerning the empirical relation between collateral and loan risk. We posit that differences in collateral characteristics, such as liquidity, may be associated with the empirical dominance of different risk-collateral relations implied by economic theory. Using credit registry data and a novel identification strategy to control for borrower and lender selection effects allows us to differentiate between the ex ante and ex post theories of collateral. We find that collateral overall is associated with lower risk premiums and higher default rates. The results indicate an important role for collateral in mitigating losses and reducing risk-taking incentives, consistent with ex post theories. Liquid collateral is associated with especially low risk premiums, and these loans perform better than those with illiquid collateral or no collateral. We also find that individual collateral types exhibit significant variation in terms of risk-collateral relations, with some consistent with ex ante theories and others with ex post theories. Our results suggest that the conflicting results in the literature may occur because different samples may be dominated by different types of collateral with different economic characteristics.

This paper offers a historical perspective on the evolution of central banks as lenders of last resort (LOLR). Countries differ in the statutory powers of the LOLR, which is the outcome of a political bargain. Collateralized LOLR lending as envisioned by Bagehot (1873) requires five key legal and institutional preconditions, all of which required political agreement. LOLR mechanisms evolved to include more than collateralized lending. LOLRs established prior to World War II, with few exceptions, followed policies that can be broadly characterized as implementing “Bagehot's Principles”: seeking to preserve systemic financial stability rather than preventing the failure of particular banks, and limiting the amount of risk absorbed by the LOLR as much as possible when providing financial assistance. After World War II, and especially after the 1970s, generous deposit insurance and ad hoc bank bailouts became the norm. The focus of bank safety net policy changed from targeting systemic stability to preventing depositor loss and the failure of banks. Statutory powers of central banks do not change much over time, or correlate with country characteristics, instead reflecting idiosyncratic political histories.