This research identifies, analyzes, and reformulates the juridical basis for the application of Justice Collaborators in murder based on Law No. 31/2014, as well as explaining the requirements and legal protection for Justice Collaborators in murder cases, reviewing the requirements and their application in legal practice in Indonesia. This research uses a normative juridical approach, namely by examining/analyzing secondary data in the form of legal materials, especially primary legal materials and secondary legal materials, by understanding law as a set of positive rules or norms in the legislative system that regulates human life. The results of the study that Justice Collaborator (JC) is an individual who is involved in a criminal act but not as the main perpetrator, and who is willing to cooperate with law enforcement to uncover larger and organized crimes. JCs have an important role in providing significant and reliable information to help law enforcement uncover major crimes. In Indonesia, JC status is regulated in various legal regulations agreed upon by the Ministry of Law and Human Rights, Attorney General's Office, Police, KPK, and LPSK. The protection of JCs is crucial, covering personal, family, and property security, as well as other rights such as a new identity and legal protection. Existing regulations allow JCs to be granted leniency or other benefits in recognition of their cooperation.