During the Great Depression, tariffs were at historic highs. Members of Congress usually engaged in informal counter-agreements in which they voted in favor of other members` preferential tariffs in order to secure the support of their own. No one has taken into account the global toll for U.S. consumers or exporters. This practice is usually called logrolling. Roosevelt and important members of his government were determined to stop the practice.   analyze the differences between the PPML and OLS estimates by Monte Carlo simulations. They indicate that PPML uses deviations from trade flow levels from their forecasts, while the OLS contains deviations from the protocol. They show that PPML tends to place more emphasis on pairs of countries with high trade volumes, which has an impact on the results.