"This report describes the numerous ways that government policy decisions can affect the freight system and, in turn, how understanding the differing concerns and priorities of governments is crucial to better consideration of the potential impacts of public policy. Using interviews with industry experts and an extensive review of documents, the research identifies current and recent policy issues with potential freight system impacts, evaluates the magnitude of the impacts, and assesses the extent to which the impacts were unexpected. Among the types of impacts identified were (1) changes in costs and revenues to freight carriers and shippers, (2) changes in freight volumes or shifts in mode, (3) changes in freight service quality, and (4) changes to freight system operations and safety. The research will promote a better understanding at all levels of government of the complex relationships inherent in public policy and foster appreciation for how public policies affect the freight transportation system."--pub. desc.