Re: Legal requirements for a law to be considered valid

Your interpretation is correct, but you leave out the fact that the law does NOT require that you endanger yourself to move over. Public servants shouldn't have to risk their lives from drivers who don't measure distance very well. If you can't move over, you're not required to do so. if you, you ought to do so regardless to whether the person is a cop or not.

Re: Legal requirements for a law to be considered valid

I don't see a problem with the law you describe, since the state has a valid interest in protecting law enforcement officers. Unlike most of us, police officers spend much of their time standing on the side of roads while traffic speeds past. They are thus far more likely than most of us to be hit by a drunk or careless driver. In fact, a disturbingly large number are injured or killed this way every year. Over the course of a career, there is a rather high chance that a police officer will actually be in such an accident, but those odds are very remote for the rest of us.

Laws which treat different groups of people differently can sometimes be successfully challenged on equal protection grounds. If the law discriminates on the basis of a suspect classification like religion, race or gender, then the government has to prove both that it has a compelling interest in the goals served by the law and that there is no other, more narrowly-tailored way to protect that interest. In a situation like this one, though, the government would only have to prove that the law serves a legitimate interest and that there is a rational basis for the distinction it draws. I think the explanation I provided in the first paragraph shows that the statute would pass this test.