Actually, I've spoken with several lawyers ($$$
) about interpreting these codes before publishing LiftLaws.com
The code states that where glass "is" used, it must be safety glass. As opposed to your statement of where glass is "supposed" to be there must be safety glass. The point of this law (every state has a safety glass law) is to avoid injury and lacerations due to broken glass.
I completely agree that not having a windshield could easily constitute a violation of 56-5-5310, however, as the code is written it cannot be definitively stated that a windshield is or is not required, that is why I left it as "unclear" on the site. Yes, I do show that windshield wipers are required.
That is in-fact the correct law for Colorado. I've spoken with several Colorado police officers about it and they have all told me that they have more important things to worry about than lift laws. For whatever that's worth...
I really appreciate the feedback (and criticism), keep it coming