Comment by epgui

Yeah, I suppose this could vary by geography, but my understanding is that in Canada, you're nearly-absolutely responsible for hitting anything in front of you, and nearly-absolutely not responsible for anything hitting you from behind.

The only exception I could think of would be if someone intentionally jumped in front of your car, or if you did a patently and clearly unsafe maneuver, but even then I think there'd be a sort of rebuttable presumption of fault.