In 2014, Lisa Cook published an article in Journal of Economic Growth titled “Violence and Economic Activity: Evidence from African American Patents, 1870–1940.” Cook studied the effect of racial violence on innovation by Black Americans over the period 1870–1940. The results of Cook’s article have been and continue to be widely cited and discussed in the media. In this article, I show that the results in Cook (2014) are not reliable, and therefore, its conclusions are uninformative.