I reread that old thread, and then skimmed the Penn State article (a bit quickly, I admit). I gotta say: I think you're overstating your case here. Certainly, the author of that article is skeptical about the 100-mile zone and makes plenty of good (and, IMO, obvious) points about why it is constitutionally suspect. But, to read your comments, you'd think that some important court somewhere has actually placed meaningful limits on immigration enforcement within that zone (outside the context of an actual border crossing). If so, I don't see where you're getting that. If that's actually in the article, could you tell us where?

To be fair, though, I think it is also true that the ACLU is too eager to talk about the "Constitution-Free Zone" as though it is fact. I also agree that people should not simply accept that the Constitution-Free Zone exists. It is definitely not that simple and what would otherwise be 4th Amendment violations should absolutely still be challenged even if they occur within the zone. There is still every opportunity for more good law on this.