How are cops supposed to know if they outgrew their seat? It also means that when they move to forward facing or a booster seat depends on the car seat you bought, not their height, (only their) age, or weight.
For older kids, here's the new rule: "A child at least 9 years old or has outgrown their booster seat AND the child can pass the "5 step test" may be restrained by a regular seatbelt, but they must be in a the back seat if possible under 13."
That's not too bad because they at least have a set age, but you still can't expect a parent to have a set of 4 booster seats ready to go to haul your kids friend's around.
Sucks, as this isn't as easy as saying it will be your responsibility and fault if the kid is injured. Odds are high this will just make a bad situation worse.
I also can't offer much of a defense of car seats. Obviously, go for safety; but it does feel that people are chasing a tail end of safety that is not really measurable. Modern cars and using seat belts have come a long long way to make vehicles safer.
There is also the interesting contrast with busses on this. Kids don't buckle up or use seat belts in school busses.
When was a kid, you were done with your car seat by elementary school so one parent could offer to carpool a minivan full of kids to/from an event.
But now that some kids need their car seat into middle school carpools are gone and every kid needs their parent to pick them up. It requires way more planning and parental involvement