A Boston Globe investigation has revealed the existence of a domestic surveillance program run by the Transportation Security Authority, or TSA, which has been surveilling U.S. citizens on planes and in airports since 2010. Under the program, called “Quiet Skies,” federal air marshals collect information about U.S. travelers, including common behavior like using the bathroom repeatedly, sleeping on flights or sweating heavily. In response, the ACLU said, “Such surveillance not only makes no sense, it is a big waste of taxpayer money and raises a number of constitutional questions.”