Susuto

A double-yellow line is a painted marking on the highway that indicates restriction against the opposing side of the highway. A major exception of the restriction is emergency maneuvers or when there is a half-to-half phase construction project on 4-lane arterials going on, not to mention contraflow lane reversal allows cars to go all one direction albeit the line restriction. Another reason for a double-yellow line is for no passing zones. Many double-yellow lines exist in the form of a solid line with a dotted line aside of it. The dotted-solid setup is often put on 5-lane arterial streets; they are placed pace-opposite in Ontario.

Check state regulations regarding overtaking vehicles in the presence of solid yellow lines. In some states, it’s not against the law to overtake vehicles in the presence of solid yellow lines if it is safe to do so. Section 3303 and 3305 of the PA driver code are examples.

http://en.wikipedia.org/wiki/Double-yellow_line

So, he shouldn’t have passed the guys.