In 1978, one of Wyoming's most infamous killings took place in Rock Springs. Rock Springs Director of Safety Ed Cantrell shot his deputy Michael Rosa, who was in the backseat of a car. Cantrell said he shot Rosa in self-defense, while others suggested that Cantrell was trying to keep Rosa from testifying about local corruption he had witnessed.
Cantrell hired Wyoming Attorney Gerry Spence and was acquitted of first-degree murder in Pinedale. Award-winning investigative journalist Rone Tempest has written about the incident in his new book, The Last Western. He sets the stage by describing Rock Springs at the time.