Generally, when approaching a light that has turned yellow, you need to slow down and prepare to stop. The yellow light is to warn you that the red is close at hand, but your obligation as a driver is to treat it the same way that you would a red light.
Of course, many people fail to do this. You don’t have to drive for long to see multiple drivers speed up at a yellow light, trying to force their way through before it turns red, instead of stopping. This is a very dangerous practice, but there is one time when it’s permissible — if you have passed the point of no return.
It’s a lot closer than people think
The authorities recognize that a light may turn yellow at a time when drivers are too close to stop safely. Trying to slam on their brakes could cause them to lose control and crash. The safest thing, then, is to keep driving through the yellow light. This is the very reason it exists, after all — to prevent drivers from having to aggressively stop at the red.
However, the point of no return is typically just about 100 feet. It can vary somewhat depending on speed, road conditions and the like, but you generally don’t need to do the math. If you’re about 100 feet from the intersection — or less — you can keep driving. Anything more and you need to stop.
The problem is that aggressive drivers may speed up with they’re far from that point of no return. This leads to red light running and severe accidents. If you are injured by one of these drivers, you may be able to seek compensation.