When the ropes tie together: international criminal legality and constitutional precommitment in the Muiña-Batalla case

Abstract

This article analyzes a judicial episode of the Supreme Court of Justice of Argentina (CSJN) comprising the Muiña (2017) and Batalla (2018) rulings. In Muiña, the CSJN granted a person convicted of crimes against humanity —offences committed by State agents during the Argentine civic-military dictatorship of 1976-1983— a sentence-computation benefit known as the 2x1, provided for in an already repealed statute, which reduces time in custody in proportion to the time spent in pretrial detention prior to conviction. Following an intense social reaction and an act of Congress establishing the "authentic interpretation" of the aforementioned rule, in Batalla the Court denied that benefit. The objective is to determine whether that denial finds support in the principle of criminal legality. Methodologically, a doctrinal, case-law and comparative analysis was employed, articulating the constitutional theory of precommitment and judicial review with the theory of the principle of legality in international criminal law. It is argued that the case does not conform to the binary scheme of constitution versus majority, but rather to a collision between two mandates of equal rank within the Argentine constitutionality block: criminal legality in its dimension of the retroactive application of the more lenient law, and the State's duty to punish crimes against humanity. It is contended that the international conception of legality —of Anglo-Saxon origin, formulated as nullum crimen sine iure— grounds the solution reached in Batalla, since it does not require a prior formal statute but prior law, and reserves its core guarantee to the non-retroactivity of criminalization, which is foreign to sentence computation. It is concluded that this reading resolves the collision with greater explanatory power than the majoritarian, rights-guaranteeing and strategic-defection readings.