Actually, the Catechism text encapsulates both retributive and deterrence arguments, though I would argue the text bears the former more strongly. The key is to

Actually, the Catechism text encapsulates both retributive and deterrence arguments, though I would argue the text bears the former more strongly. The key is to see the "outrage and violence" part not only with respect to potential violence (which might be deterred in view of capital punishment) but also the natural repercussions of injustices left festering when civil authority fails to inflict fitting punishments on wrongdoers.