PERTANGGUNG JAWABAN PIDANA MENGGUNAKAN SURAT PALSU DITINJAU DARI ASPEK KEPASTIAN HUKUM

This research examines the form of criminal liability for the use of fake letters as regulated in Article 391 of Law Number 1 of 2023 concerning the new Indonesian Criminal Code (KUHP), and its implications from the perspective of legal certainty. The crime of document forgery is not only materially harmful but also undermines public trust in the authenticity of legal documents. This study uses a normative juridical method with a statutory approach. The legal materials employed consist of primary legal materials , secondary legal materials , and tertiary legal materials .Legal materials were collected through a literature study, and analyzed qualitatively and descriptively using a deductive approach. The results indicate that a person can be held criminally liable for using a fake letter if elements of intent and unlawful purpose are proven, even if they are not the creator of the forged document. Article 391 provides a clear legal basis; however, in practice, challenges remain—particularly in proving the subjective element. Therefore, consistent law enforcement is necessary to ensure fair legal protection and certainty for the public. As a recommendation, law enforcement officers must enhance their competence in distinguishing between administrative errors and actual criminal acts, to avoid unjust criminalization and to uphold justice and legal certainty in Indonesia.