The law states that groups A B or C are exempt for reason Y.
Clearly, the intent of the law, as written, is to allow police the use of unmarked vehicles for undercover or special investigations, and those purposes ONLY.
Anyone who paid attention in 4th grade during sentence diagramming can clearly see this.
So, unless you are the subject of an ongoing undercover or special (which could have broad meaning but does not encompass a split second decision to pull you over or not pull you over for a traffic violation) investigation and you are pulled over by ANY police officer who is in an unmarked car (and, the standards for "marking" are clearly called in the statute as well, and lights and a grill commonly used by police do not meet the standard), THAT OFFICER IS ACTING UNLAWFULLY (this is stated at the beginning of the statute).
I would not cooperate with the officer, which could lead to my arrest, but that would give me an immediate chance to fight the unlawful behavior by the officer.
Now, am I guaranteed a win in court? No, but should I be granted a probable cause hearing by a judge who is fluent in English and has some modicum of respect for the law, I should easily find my motion granted and the case dropped.
The real trick would be convincing the judge to then issue a warrant for the officers arrest (unlawful detainment among other things). I don't think my chances here would be more than 1 in a metric **** ton, but I would remind the judge how many times I've been told that ignorance of the law is not a defense, and that illegal is illegal no matter who perpetrates the crime.
I'm pretty sure I'll get laughed out of court as the prosecutor has his or her tail between their legs, having been quickly bested by someone without a bar card, but with some sense of satisfaction that I was mocked on my way out of court.
At least that's what's happened the 3 other times I had cases dismissed in motions court, pro se.
I swear, lawyers are great with procedure and sometimes their familiarity with the judges and clerks has value, but they are the only people who know less about the actual law than I do.