https://phys.org/news/2018-07-private-messaging-apps-increasingly-business.html

The proliferation of digital tools that make text and email messages vanish may be welcome to Americans seeking to guard their privacy. But open government advocates fear they are being misused by public officials to conduct business in secret and evade transparency laws.

Whether communications on those platforms should be part of the public record is a growing but unsettled debate in states across the country. Updates to transparency laws lag behind rapid technological advances, and the public and private personas of state officials overlap on private smartphones and social media accounts.