The Fourth Amendment and "Domestic Military Operations":
There has been a lot of press attention recently on references in the John Yoo torture memo to another classified OLC memo apparently concluding that the Fourth Amendment does not apply to "domestic military operations." For background, see here and here .

  What to make of this depends mostly on what you think the phrase "domestic military operations" might mean, and more specifically, what "military operations" are. If "domestic military operations" refers to actual active battlefields in the United States -- think the Battle of Gettysburg, or the British attack on Washington in the War of 1812, etc. -- then I think that conclusion is very likely correct.

  Why? Here caselaw doesn't do much for us. As far as I know there is no caselaw on anything like this question. Probably as close as you can get is United States v. Verdugo-Urquidez, and that's still pretty far away. But I think the problem is that the principles of the Fourth Amendment and the principles of an active battlefield are almost 180 degrees apart from each other. Fourth Amendment rules are all about proportionality; by contrast, military strategy often requires overwhelming force. I don't know how a Fourth Amendment lawyer could be expected to weigh in on questions of military strategy to try to respect some sort of Fourth Amendment constitutional values. What would the lawyer say -- that the Army should break into enemy safehouses only during day time, for fear that breaking in at night could interrupt the enemy's "period of nighttime repose"? That they should "knock and announce" their presence before the Marines take a hill? It's hard to know how the two worlds are supposed to mix; they are just totally different.

  Or at least they are very different if "domestic military operations" is given a narrow meaning, such as an active battlefield. If the phrase has some sort of broader meaning, then you start to run into problems. Obviously, the mere fact that a war is on does not eliminate Fourth Amendment rights. Nor does the fact that the President is commanding the Executive Branch to act to protect the country mean that the Fourth Amendment doesn't apply. See, e.g., United States v. United States District Court. If the OLC memo took a contrary position, then it's pretty obviously wrong.

  As for whether the OLC memo takes (or took) such a broad reading, we just don't know. The Administration has long had a very broad view of how broadly "the battlefield" is in the GWOT, so it's possible. But we just don't know, and without that it's hard to know whether the OLC memo is objectionable.