All states have traffic laws that cover when a driver can pass another vehicle and require passing to be done safely. Here are some of the more common passing-law restrictions and requirements and some possible defenses to an unsafe or illegal passing ticket.
Generally, passing laws are of three types: rules for passing vehicles when there are multiple lanes going in the same direction, rules for passing vehicles when you must cross into an oncoming traffic lane to make the pass, and rules that prohibit passing altogether.
Laws that cover passing when crossing the centerline of the roadway is not required (where there are multiple lanes in the same direction), often say something like this:
The driver of a vehicle overtaking another vehicle proceeding in the same direction shall pass to the left thereof at a safe distance and shall not again drive to the right side of the roadway until safely clear of the overtaken vehicle.
Some state laws also require the driver who is making the pass to give an "audible signal" (honk) when passing.
When you must cross the centerline of the roadway to pass (typically, on highways with only one lane in each direction), state laws normally impose a number of restrictions to ensure passing is done only when safe. Most state laws read something like this:
No vehicle shall be driven to the left side of the center of the roadway in overtaking and passing another vehicle proceeding in the same direction unless such left side is clearly visible and free of oncoming traffic for a sufficient distance ahead to permit such overtaking and passing to be completely made without interfering with the safe operation of any vehicle approaching from the opposite direction or any vehicle overtaken. In every event, the overtaking vehicle must return to the right-hand side of the roadway before coming within 100 feet of any vehicle approaching from the opposite direction.
Additionally, most state laws prohibit crossing the centerline to pass when:
The details of state laws vary somewhat. But most states have laws that roughly mirror these examples.
All states have no passing zones. Generally, no passing zones are areas where the department of transportation (or the relevant government entity) has determined that passing is not safe. Generally, state laws require no-passing zones to be identified with signs or appropriate pavement markings (normally, solid double yellow lines).
As with contesting any traffic ticket, fighting an unsafe passing ticket begins with looking up the statute you're accused of violating. The number of the statute (such as "W.Va. Code, § 17C-7-7") should be written somewhere on your ticket. With the code section, it's typically easy to find the text of the statute with an internet search. Reading the text of the statute should give you a good idea of the kinds of defenses that court work.
For instance, with many statutes, proving a violation requires the government to show that the driver's actions were unsafe. Whether a particular action of a driver was reasonably safe is a judgment call on the part of the officer who issued the ticket. So, in defending against this kind of ticket, you might want to focus on factors such as good road conditions and clear weather that tend to make vehicle maneuvering safer. And, if the officer wasn't in a position to view the situation clearly, you might want to bring this information out in cross-examination of the officer or in your own testimony.