Although nearly invisible to the public, millions of hobbyists around the world have for decades played an important role in local journalism. Whether it is a bank robbery, train derailment, car accident, or the rescue of a cat stuck in a tree, chances are police scanner listeners will hear it and some will tip off journalists. These “if it bleeds it leads” stories are, for better or worse, an important part of local television newscasts and other forms of local news. Long before internet content creators and social media sites, scanner hobbyists formed groups that created information feeds to share with each other and the public. In the 1990s, for example, a group of listeners in Colorado started a Twitter-like news sharing service for its 500 members, sending out updates over a network of alphanumeric pagers. Mountain News Net continues its work today using modern technology. What is perhaps least known about scanner hobbyists is that Mountain News Net and certain other listener groups relied on journalistic-style principles and news values in the material they shared. Mountain News Net’s small team of “dispatchers” rely on well-understood guidelines for their feed, gatekeeping what is sent to their members. Local News providers in Colorado also work with the group to get access to news tips. Indeed, there is much to be heard on a police scanner, usually small dramas that unfold in real-time, providing a record of events from the first responder perspective. Listening to these stories can be so compelling some listeners won’t go anywhere without their radios. Jack Dorsey was a scanner listener as a child, and he said the experience inspired him to help create Twitter. This dissertation brings to light this unexplored world of public safety radio and its close connections to journalism and user-generated content. The nearly century-old hobby is examined in a historical context, and through semi-structured interviews with Members of the Mountain News Net and other key informants provides a deep explanation of how these pre-internet citizen journalists came to be and the role they play today.