I've got 35% on my windows and was told that they just changed the limit in NSW to allow even darker - not sure to what level, but that was the word. If they're going around with light meters, you gotta wonder ...
Years ago I went and moved to Canberra for work, and as part of that, I had to get my car pit-inspected. It was a Bitsoshitty L300 that was completely stock standard. So the guys look it over and it goes something like this:
Ben: "Hey, these windows look like they're tinted".
Bill: "I'll bring the light meter, we'll show this doof we don't like his NSWelsh-kind here"
Ben: "Excuse me sir, we think your windows are tinted and we're going to test them"
Me: "Fine, there's no tint on them, but test away."
Bill (operating the meter): "Check this out Ben"
Here, Bill shows Ben the light meter reading the light source directly without my window inbetween. He then shows Ben the light meter reading the light source THROUGH my window and passing more light than when the window wasn't there.
Mr Flower Pot Man then tried to accuse me of tampering with his equipment, his test, and warned me that I could be fined for it.
Moral of the story: light meters aren't always accurate.
Corollary: authorised representatives of government agencies will try anything to make you look bad because that's what scores points in their own books. In the long run, departmental employees are after statistics, and they won't let an obvious fact stand in the way of another number.