In Aranyosi, the CJEU ruled that a judicial authority in the executing member state may refuse to enforce a European Arrest Warrant if there is a real risk of inhuman and degrading treatments in the prisons of the issuing state. This judgement has been welcomed as a move away from the ‘deification of mutual trust’ dominating earlier case law. Surprisingly, the same finding has not yet been extended to the interpretation of EU legislative instruments on mutual recognition of final sentencing decisions (including prison terms). Indications from recent case law, by contrast, show a rigid approach to interpreting the obligation of mutual recognition in this area. In particular, the Court has left little room for humanitarian and penological concerns while dealing with the cross-border enforcement of sentences. This paper unravels the rationale behind this approach, by highlighting the peculiar way in which mutual trust has been framed in this specific sub-field of judicial cooperation.