The document summarizes research examining the relationship between tornado warning false alarm rates (FAR) and tornado casualties. It finds that higher recent false alarm rates are associated with more tornado injuries and fatalities, after controlling for tornado and demographic characteristics. A one standard deviation increase in the local one-year FAR is estimated to increase injuries by 12-14% and fatalities by 13-18%. The results provide empirical evidence that higher false alarm rates may reduce the credibility of and response to tornado warnings.