LIBOR ’ s Poker : Interbank Borrowing Costs and Strategic Reporting ∗

The recent LIBOR scandals have demonstrated that the panel banks did not report in good faith, leading some to question whether LIBOR was ever accurate. This article derives the equilibrium LIBOR reporting strategy and quantifies the LIBOR bias. It finds that the current trimming mechanism cannot prevent LIBOR rigging, although the LIBOR gets less biased when the cross-sectional dispersion of the panel banks’ borrowing costs becomes lower. This explains why LIBOR earned wide adoption before the financial crisis. Additionally, signaling caps LIBOR. However, hiding individual banks’ reports to the market blocks signaling altogether. Finally, there exists a mechanism that induces truthful reporting.