Citizens' U.S. Border Crossings Tracked The federal government has been using its system of border checkpoints to greatly expand a database on travelers entering the country by collecting information on all U.S. citizens crossing by land, compiling data that will be stored for 15 years and may be used in criminal and intelligence investigations. Officials say the Border Crossing Information system, disclosed last month by the Department of Homeland Security in a Federal Register notice, is part of a broader effort to guard against terrorist threats. It also reflects the growing number of government systems containing personal information on Americans that can be shared for a broad range of law enforcement and intelligence purposes, some of which are exempt from some Privacy Act protections....