One of Caruthers' most important decisions on the court was his opinion in "Rippy v. State" (1858), which involved killing in self-defense. In this decision, he rejected a literal interpretation of a statement in Judge John Catron's opinion in "Grainger v. State", issued three decades earlier, that suggested a person did not need sufficient grounds to kill in self-defense, but merely needed to testify that there was imminent danger. Caruthers' opinion reinstated the "sufficient grounds" rule. He wrote of "Grainger", "no case has been more perverted and misapplied by advocates and juries."