Several states in the US have laws on the books allowing bikers to conditionally ignore stop signs, but typically to "downgrade" a stop sign to a yield sign. https://en.m.wikipedia.org/wiki/Idaho_stop

The basic premise is that because a bike is slow enough, and the stopping distance of a bike at speed is short enough, a bike can approach an intersection, make a judgment call on if they need to stop, and if they don't expect to get hit, they can cross without coming to a full stop first like a car does.