NEW YORK (AP) — The case of a mentally ill homeless veteran who died in a 100-degree Rikers Island jail cell starkly illustrates the dangers of extreme heat in lockups, an issue facing prisons across the nation as the inmate population gets older and more heavily medicated — and more at risk of overheating.

Inmate advocates point out that many prisoners exposed to high temperatures are unable to cool themselves — by taking a cold shower or by sitting in an air-conditioned room — in a way people living outside prison walls regularly do.