T This research discusses the criminal act of participating in the use of a letter suspected of being fake according to article 263 paragraph (2) of the criminal code in conjunction with article 55 paragraph (1) 1 of the criminal code as applied in decision number 873/pid.b/2023/pn smr. the problem examined in this research is whether the judge\\\'s considerations and decisions are in accordance with the provisions of article 263 paragraph (2) of the criminal code in conjunction with article 55 paragraph (1) 1 of the criminal code and how the categories and conditions for participation (inclusion) are applied in the decision. this research uses a normative legal research method with a descriptive research nature, through a literature review of primary, secondary, and tertiary legal materials. data are analyzed qualitatively with deductive conclusions. the results of the study show that in decision number 873/pid.b/2023/pn smr, the judge stated that the defendant committed a crime using a letter that was allegedly fake without sufficient evidence regarding the element of intent as required in article 263 paragraph (2) of the criminal code. in addition, the application of article 55 paragraph (1) point 1 of the criminal code regarding involvement has not fully considered the categories and conditions and according to criminal law doctrine, especially regarding the existence of an active role and joint intent. therefore, the judge\\\'s considerations in the decision are considered not to be fully in line with the provisions of applicable criminal law.