Andy McCarthy defends his work on the Patriot Act:

Concerns about “John Doe” warrants i.e., roving wiretap authorizations that do not name a specific person or place to be surveilled have been discussed since 2001... although we’ve now had this provision for close to a decade, civil liberties advocates like Mr. Friedersdorf and Cato’s Julian Sanchez still have to couch their objections in the subjunctive mood: the warrants “raise the possibility” of overbreadth abuses “disturbingly similar to the ‘general warrants’” prohibited by the Fourth Amendment. That is, although the Patriot Act has been examined, debated, and reauthorized a number of times since its initial passage shortly after 9/11, critics still have no concrete record that roving taps have been systematically abused, so they have to raise potential abuses that never seem to materialize.

In a lengthy response, Julian Sanchez objects:

Just in fiscal 2008, the FBI alone collected 878,383 hours (or just over 100 years) of audio, much of it in foreign languages; 1,610,091 pages of text; and 28,795,212 electronic files. A recent review of FBI backlogs by the Office of the Inspector General found that fully a quarter of the audio collected between 2003 and 2008 remained unreviewed (including 6 percent of counterterror acquisitions and 31 percent of counterintelligence acquisitions, the two categories covered by FISA wiretaps). Let that sink in for a second: They have literally years worth of audio material alone that the Bureau itself can't be sure of the contents of, never mind any kind of independent oversight body.

...[M]eaningful after-the-fact oversight of the fruits of FISA surveillance is a chimera. The issue is not just that the safeguards here are less stringent on the front endin this case, the absence of the requirement that roving taps name each individual targetbut that many of the the back end safeguards are missing too. Sometimes, of course, it is possible to catch abuses on the backend, but the reality is that if they do occur, there's a good chance we won't know about it.

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