Wading through all the "hyperbole" (my new favorite word BTW) of the initial article, the only real issue I see is the possibility of "political profiling"...
If in fact failure to use a turn signal warrents a citation in LA, and if in fact the officer actually addressed the failure to use a turn signal, then I really see no wrongdoing.
But, if the officer never addressed the turn signal issue and only concentrated on the presence of firearms through the duration of the stop, I see a high probability of profiling, given the nature of the citizen's bumper stickers.
One reason why the only sticker on my truck is the Coast Guard decal I have to display in order to drive on base...
I've never seen a Brady-bunch-type say "You know what? I've always thought guns were evil, but after seeing that 'Guns don't kill people, people kill people!' bumper sticker I think I'll join the NRA now."