I learned by experience that green lights mean nothing. I've had too many cars run a red as I was crossing at the green...laws, traffic regulations, signs, lights do not guarantee your safety. The most important thing is awareness of what's happening around you. Forget the laws and learn to read the flow of traffic. Sometimes you have to break the law to protect yourself. If it's behind you then you have no control over it,...if it's on your right/left, or in front of you then you should be able to see it.