4-way Stops, or Lack Thereof

I was on my way to do my weekly grocery shopping. I come to the 4-way stop down the street. The car to my right stopped before I did so they obviously have the right of way. What the truck behind them failed to notice was that you have to pull up to the stop line, stop and then proceed. Not stay stopped where they were behind the car in front of them and then disregard the rules of right of way at a 4-way stop. I technically had the right of way after the car since I stopped at the stop line just after the car did and before the truck did.

Apparently he had a case of 'not so common' common sense that day....