Violence is a recurring motif throughout Running Loose. From the beginning, the novel hints at violence in the small town of Trout, Idaho. In Chapter 2, Louie and Carter find blood at the Buckhorn restaurant, evidence of a brawl from the night before. Football practice itself is a violent and physically demanding ordeal, with some players vomiting from the exertion. Coach Lednecky is portrayed as aggressive, warning players that breaking the rules will result in expulsion from the team. Becky dies in a violent accident, driving off a bridge, leading Louie to react with more violence as he is Coping with Grief and Loss: He chops down a tree and destroys the plaque dedicated to her.

Violence is embodied in the character of Boomer, who is both a victim and perpetrator. Boomer is abused by his father, who “almost [beats] him senseless” (10) for swearing and once beat him up on his birthday for lying, even throwing away his presents. This harsh upbringing has shaped Boomer into a violent individual himself. He is large and intimidating, and Louie admits Boomer “scares [him] to death” (8). In Chapter 5, he punches Louie in the face, and in Chapter 7, he attacks him in his car, clinging to it as Louie drives off.