Probable Cause

PROBABLE CAUSE….I was reading Richard Posner’s article in the New Republic this morning not because I was interested in his judicial philosophy, but because I was interested in what he had to say about the NSA’s domestic spying program. Here’s the relevant paragraph:

Suppose a phone number in the United States is discovered on a rolodex in an Al Qaeda hideout in Yemen. Wouldn’t you want the NSA to intercept all calls, especially international, to or from that U.S. number and scrutinize them for suspicious content? Yet the mere fact that a suspected or even a known terrorist has a U.S. phone number in his possession would not create probable cause to believe the owner of that phone also a terrorist; probably most phone conversations of terrorists are not with other terrorists. The government can’t get a FISA warrant just to find out whether someone is a terrorist, though that’s what it most needs to know.

Does this sound right? Being on a terrorist’s speed dial actually strikes me as a pretty good example of probable cause, especially since the FISA court appears to have a fairly expansive view of what constitutes probable cause. But are al-Qaeda rolodexes really a good example anyway? Since the NSA program started up very quickly after 9/11, I doubt that it’s based on physical evidence from Yemeni caves, which is probably fairly uncommon. It’s far more likely that it’s based on actual communications intercepts of some kind. In that vein, here’s what I’ve been assuming all along about how FISA warrants work in real life:

  • Al-Qaeda suspect in Yemen calls someone in Pakistan. No problem. We can intercept without a warrant.

  • Al-Qaeda suspect in Yemen calls Mr. X in Chicago. Again, no problem. The FISA court would issue a warrant without a fuss.

  • NSA wants to tap Mr. X’s phone to find out who else he’s talking to. Since Mr. X is known to have talked to an al-Qaeda suspect in Yemen, this is probable cause and the FISA court would issue a warrant. At a minimum, the court would certainly issue a warrant if the previous conversation had been even remotely suspicious.

    Note that I’m assuming there’s a considerable difference between a national security investigation and, say, a mafia investigation. If Mr. X gets a call from a suspected mob boss, there’s a pretty good chance that Mr. X is an innocent party ? just an ordinary butcher, baker, or flower delivery guy. But if Mr. X gets a call from a cave in Yemen, there’s a pretty good chance he’s not an innocent party. Unlike the mob example, phone calls from Yemeni terrorists would probably cause a judge to agree that there’s probable cause to believe that Mr. X might be an affiliate of a terrorist organization.

In other words, I’m working under the assumption that the FISA court would consider it “probable cause” that a U.S. citizen is an agent of al-Qaeda if that citizen is known to have communicated with al-Qaeda suspects overseas. A warrant against such a person would be issued routinely.

However, the NSA’s secret program is directed solely at U.S. citizens whom the government doesn’t have probable cause to believe are agents of al-Qaeda. This means the evidence they do have isn’t phone calls or rolodexes. It’s something much fuzzier, something that even a notoriously compliant, post-9/11 FISA court wouldn’t consider adequate as probable cause. Perhaps something like this.

Of course, these are just assumptions on my part, since I don’t know the inner workings of the FISA court or the legal definition of probable cause in international terrorist investigations. That’s why I’m throwing them out for comment. Question: Do they sound reasonable? Or am I overlooking something significant?