I think relevance is very hard to codify. It seems simple, and if one took a very simple codification and looked at some of the evidence text, they will have, maybe in a short sentence, their definition of relevance. Maybe that would be fine, but....
I grew up and I was a prosecutor in the days before we had the rape shield laws. There's only one thing in my life that I've ever vowed to try to see changed, and that was the way rape victims used to be treated in the 1960s and 1970s. That did get changed with the rape shield laws, but they're very complex and complicated, I think. All that was required was something to tell the judges and make the judges rule on relevance, because all the rape shield laws are trying to do is say that irrelevant evidence is not admissible, yet when you look at that, you see how complex those sections are. I think it's difficult to legislate something like that; it'd be like legislating what is good and what is bad. You can take specific instances as to what is bad and make it a crime, but to legislate relevance is difficult.
I think that there could perhaps be some prompts that it doesn't mean a semblance of relevance, for instance, or a hint of relevance, but clear relevance. Beyond that, my experience tells me that it would be difficult to draft such legislation.