Gen. Keith Alexander, director of the National Security Agency, testified before the House Intelligence Committee on Tuesday and vigorously defended collection of telephonic metadata. Alexander assured the committee that, despite widespread public worries about the government collecting private information on innocent Americans, there are ample safeguards in place to protect civil liberties. "These programs are limited, focused and subject to rigorous oversight," Alexander told Congress. "They have distinct purposes and oversight mechanisms. We have rigorous training programs for our analysts and their supervisors to understand their responsibilities regarding compliance."

These programs are limited, focused and subject to rigorous oversight.

Alexander also reiterated the vital role these metadata-based programs have filled in protecting the U.S. and its allies from terrorist attacks. "In recent years," Alexander said, "the information gathered from these programs provided the U.S. government with critical leads to help prevent over 50 potential terrorist events in more than 20 countries around the world." Metadata collection was important to those successes.

Despite Alexander's reassurances and claimed benefits for the metadata program, legitimate concerns remain that these efforts have the potential to encourage ever more expansive data collection by the government. If phone records are useful now in stopping terrorist attacks, how long before politicians and bureaucrats decide archiving the entire phone call would be even more useful? How long before the limitations and safeguards now in place are set aside? This remains the unavoidable point of collision between individual privacy rights and national security.

Deputy Attorney General James Cole testified on that issue, claiming that "under the law, the Fourth Amendment does not apply to these records." He cited a previous Supreme Court case saying that records without content (e.g., phone numbers, not conversations) aren't covered because there is no reasonable expectation of privacy. As a matter of law, Cole is right because Americans share their phone records with the phone company, but that doesn't obviate the ever-present temptation to abuse any unusual level of access to information about individual Americans.

Cole admitted that mistakes are occasionally made and that the wrong person is sometimes targeted, but claimed such mistakes are quickly removed from the system. Targeting an innocent citizen, however, is the fundamental fear of most Americans regarding NSA metadata collection. Rep. Jim Sensenbrenner, R-Wis., an original author of the Patriot Act (which initiated these programs), makes clear that such fears are well-grounded. Sensenbrenner pointed out that under the Obama administration's interpretation of the Patriot Act and the role of the Foreign Intelligence Surveillance Act court (which grants surveillance requests) process, an American citizen who believes he or she has been incorrectly targeted by the NSA cannot seek redress in a public court.

Without extremely rigorous accountability, the judicial process surrounding metadata collection and targeting of citizens could degenerate into something reminiscent of England's Star Chamber. That's not a reassuring prospect at a time when the IRS targeting of President Obama's perceived political and media opponents is front-page news.