[Sarge]

I receved this PM from Ducky 2.0T:
I can't post in the "Ask the law question" but I thought your response was against the actual code for PA.

Section 3304(a)
Overtaking vehicles on the right.
General rule - The drive of a vehicle may overtake and pass upon the right of another vehicle only under one of the following conditions:
i. When the vehicle overtaken is making or about to make a left turn, except that such movement shall not be made by driving off the berm or shoulder of the highway.
ii. Upon a roadway with unobstructed pavement of sufficient width for two or more line of vehicles moving lawfully in the direction being traveled by the overtaken vehicle. , except that such movement shall not be made by driving off the roadway.

3304(a)(ii) makes it seems as though passing on the right is acceptable on a highway.

New Jersey has something similar:
New Jersey Statute
39:4-85. Passing to left when overtaking; passing when in lines; signalling to pass; passing upon right
The driver of a vehicle overtaking another vehicle proceeding in the same direction shall pass at a safe distance to the left thereof and shall not again drive to the right side of the roadway until safely clear of the overtaken vehicle. If vehicles on the roadway are moving in two or more substantially continuous lines, the provisions of this paragraph and section 39:4-87 of this Title shall not be considered as prohibiting the vehicles in one line overtaking and passing the vehicles in another line either upon the right or left, nor shall those provisions be construed to prohibit drivers overtaking and passing upon the right another vehicle which is making or about to make a left turn.

I checked with my traffic guru and he told me that these are recent changes made to account for modern interstate highways that enter and exit from both sides of the road.