Zoran Milich / Reuters

Privacy advocates were right all along: The costs of one of the most controversial spy programs revealed by Edward Snowden far outweighed its benefits. That’s obvious from a 103-page study of recent efforts to log, store, and search phone metadata––e.g., the time a call was made, its duration, and the phone numbers involved––about most calls that Americans made or received.

Researchers at the congressionally created Privacy and Civil Liberties Oversight Board found that from 2015 to 2019, the NSA’s call-metadata program cost taxpayers $100 million. “Only twice during that four-year period did the program generate unique information that the F.B.I. did not already possess,” reported Charlie Savage of The New York Times, who read a copy of the findings and went on to quote a passage characterizing those two pieces of unique information: “Based on one report, F.B.I. vetted an individual, but, after vetting, determined that no further action was warranted. The second report provided unique information about a telephone number, previously known to U.S. authorities, which led to the opening of a foreign intelligence investigation.”

The NSA shuttered the program in 2019, due in part to the fact that it repeatedly collected more data than was legally permissible. The law that allows the NSA to search the data trove, moreover, expires next month, on March 15. But the Trump administration wants Congress to reauthorize the metadata program permanently, giving the NSA the discretion to restart it at any time and run it indefinitely.

That’s a bad idea for reasons beyond its dismal return on investment. Fundamentally, the program is impossible to responsibly oversee—even after a 2015 reform that required judges to sign off on spy-agency queries.

Savage explained that in 2018, “the N.S.A. obtained 14 court orders, but gathered 434 million call detail records involving 19 million phone numbers.” At that scale, the need to get a judge’s okay doesn’t offer much protection to citizens.

Had Donald Trump supporters understood this program in 2016, many would not have trusted the Obama administration to refrain from abusing it. Same goes for Bernie Sanders supporters and the Trump administration today.

And one needn’t even mistrust American politicians to object.

A centralized, searchable database of this sort is in itself a security risk. A foreign state that gains access to that data could map the social networks of high-ranking administration officials and their families, members of Congress, nuclear scientists, business leaders in industries with foreign competition, and more. National security would arguably be better protected if the U.S. government were forcing telecom companies to destroy its troves of data.

If ever there were a case for letting authorization of a national-security program expire, this is it: The expense to taxpayers is great, the benefits meager, and the potential for abuses tremendous. But once an authority is given to the executive branch, presidents are loath to let it lapse.

Congress should ignore the Trump administration’s preference and return the country to a place where the private communications of Americans are not stored for the federal government and its spies.

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