Nonsense. The Constitution is a charter document for the U.S. Federal government. These city officials could have hauled the couple out and raped and shot them, and they wouldn't have violated the Constitution. Only Federal agents/officials can do that. The city officials would have broken other laws, but not the U.S. Constitution because it places no restrictions on local governments. (Rather the opposite - cf. the 9th amendment.)
Simply not true. That’s what incorporation is all about. The first amendment applies to everything congress does and also applies to everything your local dog-catcher does.
http://en.wikipedia.org/wiki/Incorporation_of_the_Bill_of_Rights