Why The NSA's Surveillance Is Unconstitutional
Constitutional law prof Randy E. Barnett writes at the WSJ that Congress or the courts should put a stop to the NSA's unreasonable and unconstitutional data seizures. And there's more:

The Consumer Financial Protection Bureau, created by the 2010 Dodd-Frank financial reform, is compiling a massive database of citizens' personal information--including monthly credit-card, mortgage, car and other payments--ostensibly to protect consumers from abuses by financial institutions.

All of this dangerously violates the most fundamental principles of our republican form of government. The Fourth Amendment has two parts: First, "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated." Second, that "no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."

By banning unreasonable "seizures" of a person's "papers," the Fourth Amendment clearly protects what we today call "informational privacy." Rather than seizing the private papers of individual citizens, the NSA and CFPB programs instead seize the records of the private communications companies with which citizens do business under contractual "terms of service." These contracts do not authorize data-sharing with the government. Indeed, these private companies have insisted that they be compelled by statute and warrant to produce their records so as not to be accused of breaching their contracts and willingly betraying their customers' trust.

...In a republican government based on popular sovereignty, the people are the principals or masters and those in government are merely their agents or servants. For the people to control their servants, however, they must know what their servants are doing.

The secrecy of these programs makes it impossible to hold elected officials and appointed bureaucrats accountable. Relying solely on internal governmental checks violates the fundamental constitutional principle that the sovereign people must be the ultimate external judge of their servants' conduct in office. Yet such judgment and control is impossible without the information that such secret programs conceal. Had it not been for recent leaks, the American public would have no idea of the existence of these programs, and we still cannot be certain of their scope.