The district court correctly dismissed this suit, invoking Younger abstention. Plaintiff sought to enjoin the defendant district attorney from prosecuting it in state court for employing a vendor to make harassing collection calls in violation of state law. The four Younger factors all weighed in favor of abstention. The state action was ongoing as no proceedings of substance had yet occurred in the federal suit. Contrary to the plaintiff’s contention, the district attorney’s prosecution for violation of non-preempted state laws governing debt collection practices was not a prohibited exercise of visitorial powers. Plaintiff could raise its federal defense in the state court proceeding. The injunction that plaintiff sought from the federal court would interfere with the state court proceeding.