His choice to.continue…
His choice to.continue driving without clear outside visibility is criminal negligence in many jurisdictions. Cold or not, you cannot be a hazard to others on or near the roads. Heaters on internal combustion vehicles also have been known to fail sometimes in cold weather, so this is not new. Sadly, nor is the driver not operating the vehicle in a safe manner. Law enforcement should provide the driver a reminder to always operate your vehicle in a safe manner in the form of a ticket.