state laws prevent shutting off anyone's heat , even if they don't pay their bill.
To a certain extent, yes. there have been a very few instances of tragedies related to this sort of thing in years past, and I think that most states have passed laws forbidding the termination of essential services during periods of extreme weather and temperature. I don't think, however, that this is something that people with nefarious intent can exploit forever. Long-term nonpayments are investigated and services are terminated when it's clear that no danger or harm will result from it.
This is, of course, completely different from the national scandal that has erupted over the past several years in France where hundreds of elderly people have died in the heat due to neglectful and selfish children off on vacation.