Apparently, the police who accompanied the SEIU protesters to the private residence of Greg Baer were "shadowing" the protesters, not escorting the protesters. Well, that certainly makes it all better. The DC and Chevy Chase police officers really help to clarify the situation. In the front side of the interview, they talk about coordinating with each other and the protesters' liaison; of course, toward the end of the interview the Chevy Chase guy says that the protesters didn't coordinate with a liaison because they didn't want the police there. Okay. The officers also state that the DC police did not escort/shadow the protesters into Maryland. They had a smooth, coordinated hand-off with the Maryland police at the state line...except that the Maryland police did not make any arrests because they arrived after the protest started breaking up.
All in all, not a great performance by the police. And the verbal wrangling over trespass/disorderly conduct esoterica comes out as pretty weak when contrasted with the video of the protesters on this guy's lawn. And while I may have to further ameliorate my comments on the police, the demeanor of the mob does nothing to negate the concerns expressed in the thought experiment.
BONUS: If you've ever doubted Mongo's Rule #1*, ever thought that the 2nd Amendment did not establish an individual right to bear arms, or ever thought that the citizenry needs no access to private weapons because the police provide that protection, listen to the police officer from about 09:12 to 09:20. That pretty much says it all.
*If you don't have a gun, you're chum.