How does chat restriction work

Pretty straight forward question - I've never actually been punished by the system nor chat restricted but I'd like to know - let's say I'm playing a ranked game with a player who is chat restricted; is there a way for me to know that they are? It definitely puts the whole team at a disadvantage if you can't communicate.

I typically tend to assume that players just refuse to communicate and therefore report them accordingly, but the thought popped into my head - what if they are unable to since that is part of the punishments?