The Prohibition of Reformatio in Peius in the Investigation Phase?

Abstract

Csongor Herke’s study examines the principle of reformatio in peius — the prohibition of worsening a defendant’s position — within criminal proceedings, focusing on its absence during the investigation phase. The author notes that while this protection exists in appellate and extraordinary legal remedies, it does not apply in preliminary investigations, potentially undermining legal certainty and the defendant’s right to effective defense. Herke explores the theoretical background of prosecutorial discretion and the principles of legality and opportunity, tracing their evolution and interplay in modern criminal procedure. He concludes that introducing a limited form of the prohibition of aggravation into the investigation phase would enhance the rule of law and the protection of individual rights.