The FCC are currently investigating Verizon’s “mass call event” problems related to recent snow storms in DC and Maryland. The carrier failed to patch through multiple 911 calls during recent weather events, resulting in trapped motorists in dangerous conditions.
Some parts of the Baltimore-DC area received up to 12 inches of snow on and around January 26 and the resulting traffic problems, flight back-ups, and dangerous conditions resulted in a snarl of traffic on the highways and some casualties.
Why Verizon got singled out is beyond the scope of the hearing but presumably they were the only carrier overloaded enough to fail that evening.