Doubtful. Here's a pretty interesting link:
LINK
A little knowledge is a dangerous thing. The article is not actually wrong, it is however NOT an accurate portrayal of the actual implementation of it, but a string of exceptional situations trying to string itself into an argument that the law means nothing -- it is just a lawyer's intellectual argument in a thesis paper that has no real relationship to the ACTUAL policy controls or directives under which Commanders and Provost Marshals operate.
Anyone relying on that article for an idea about how Posse Comitatus is trained in pre-command courses and the expectations MACOM CGs have about how their subordinate commanders will use their MP assets would be sorely mistaken. An O6 commander who actually implemented Posse Comitatus as described in that article in a CONUS civil situation would be retiring shortly afterward, though a two-star ring-knocker would no doubt succeed in blaming his SJA for the boo-boo and still get his third star (after ignoring the JAG's words of warning, of course).
There really is no exception that would fit the situation at Rucker. Someone screwed the pooch big-time and someone will end up paying for it by ritual career immolation. It is remotely possible that it may be the same person in both cases, though I have a rather cynical view of the probabilities of that.
