Judicial procedures are fundamentally based on cooperation between judicial authorities, forming an interconnected system. Iraqi Code of Criminal Procedure No. 23 of 1971 provides a clear framework for filing criminal complaints and initiating investigations with the parties involved to verify the allegations. Undoubtedly, this responsibility primarily falls on the judicial investigator, but under the supervision of the investigating judge, who hears the statements of the parties, collects and examines evidence, and refers the case to the competent court or decides on it in specific cases. A careful examination of the Iraqi Code of Criminal Procedure No. 23 of 1971 reveals a close overlap of authority between the investigator and the judge regarding the receipt of complaints, as stated in Article 1: (The criminal case is initiated by an oral or written complaint submitted to the investigating judge or the investigator…) This explains the possibility of submitting the case to either the judge or the investigator, without restricting it to one authority. Naturally, this does not grant the investigator complete freedom in receiving complaints; rather, their work remains subject to the direct supervision of the investigating judge, as the higher judicial authority. Article 47 of the same law also allows an informer to submit a report to either the judge or the investigator in the event of a crime committed against them, or if they become aware of a crime that should trigger proceedings without filing a formal complaint, or in the case of a suspected death. This addresses the process of initiating complaints and reporting crimes. In other aspects, the investigator possesses powers similar to those of the investigating judge in conducting inquiries, including visiting the crime scene, performing necessary procedures to preserve physical evidence, seizing tools of the crime, recording statements of suspects and witnesses, and collecting information from anyone believed to have relevant knowledge about the crime. The investigator also plays a role in notifying witnesses and recording observations that may affect their competence to testify, or visiting the witness to record their statement if health or other obstacles prevent their attendance. These powers are not limited to this scope, as they extend to other areas such as searches, as stipulated in Article 72(b): (Searches are conducted by the investigating judge or the investigator…) Similarly, Article 83(a) provides that access to papers or personal items is only permitted through the investigating judge, the investigator, or the public prosecutor, which clearly demonstrates the shared authority of both positions. One of the most distinctive powers of the investigating judge is issuing arrest warrants, which the Iraqi legislator rightly emphasized, considering that arrest restricts a person’s liberty and must therefore be authorized by a higher legal authority (the investigating judge). While the investigator’s role is similar to that of the judge in other aspects, it is not shared when it comes to detaining the accused. However, an exception allows the investigator in remote areas, far from the judge’s office, to decide on detentions in felony cases and release on bail in misdemeanors, provided the decision is submitted to the judge as soon as possible. In conclusion, the judicial investigator possesses shared, similar, and restricted authority simultaneously, reflecting the cooperative nature of the legal system between the investigator and the judge. Zaid Fadhil Al-Mustaqbal University The First University in Iraq