It is legal according to Title 75 of the PA vehicle code. No Passing zones must be clearly marked by signs designating the beginning and the end of the zone. The drivers manual was revised to say "should not pass on a double yellow" in October 2003 to clarify this.
it is legal in Pennsylvania & Vermont. idk about any other states... usually i think of... anything yellow in driving = recommendations/warning. White = law. It is illegal to pass on the shoulder. & it is illegal before tunnels or hills / obstacles etc.
No, it is illegal to cross a solid yellow line. A solid line indicates that there is some road condition which inhibits your ability to see on-coming vehicles and thus be able to pass the car safely without risking a collision.
No, it is illegal to pass someone across a double yellow line on a two lane road. The line must be dashed on your side in order to make a legal pass. Generally you should wait until the line changes/goes away but if nobody's around, there's usually no harm in passing on double yellows.
There is nothing in the vehicle code which pertains to double yellow lines. No passing zones must be clearly posted. Read title 75 section 3305: Limitations on overataking on left. Vehicle code is what officers must cite from.