By *could*, do you mean that we can't absolutely prove that that sort of improbable riot won't happen?
Okay, I don't live in Toronto, and perhaps I'm optimistic in a seriously low-bar sort of way.
But don't you think Rob's shuffling off of his mortal coil would be unlikely to result in riots, and much more likely to result in FN moping around inertly, lamenting the loss of Rob and waiting for the next man-child-bully-progress-ruining-inexplicable-vote-getter to appear? (My fear is that the Next One is nobody we've ever heard of, unrelated to the Fords, about to be pushed on to the stage by some Kouvalis-wannabe, and that the Next One is just a wee bit more self-disciplined than Rob.)
If Rob checks out well in advance of his three score and ten, I think there would be lots of quasi-incendiary and horribly offensive crap posted on Facebook and other web sites, but close-to-zero physical harm to persons or things.