It has been argued that the current state of scientific research on the general problems of the implementation of the defence function, in particular during pre-trial investigation, in the science of criminal procedure is characterised by a significant number of monographs and scientific publications, in which scientists have quite meaningfully and deeply worked out the issues of the essence and content of the defence function, the subjects of its implementation, and the general forms and methods of carrying out the relevant procedural activity. However, certain issues of the specifics of the implementation of this function in the process of investigation conducted under martial law (admission of a defence lawyer, including remote counsel, collection and submission of evidence, appeal against actions and decisions of investigation bodies, application of security measures and preventive measures to the suspect, accused, and conducting investigative (search) actions under martial law, etc.) require further elaboration. And some issues (related to the introduction of restrictions on the constitutional rights and freedoms of the suspect, accused, etc., the peculiarity of the forms of control over compliance with the law in criminal proceedings, etc.) require the elaboration of proposals for clarification and improvement of the legal norms that regulate them.
The features of the implementation of the function of protection during the pre-trial investigation of war crimes under martial law have been disclosed through the prism: definition and change of jurisdiction; obtaining information about possible cases of war crimes under conditions of time shortage and/or access to the source of information, in particular due to the fact that the settlement is under occupation; recognition as victims in proceedings on war crimes against a person and against property only of persons protected by international humanitarian law; specifying the content of the subject matter and the limits of proof in this category of proceedings; the procedural status of the perpetrators of war crimes; specifics of the special pre-trial investigation procedure; cooperation with the International Criminal Court. It has been emphasised that the implementation of the defence function during the pre-trial investigation of war crimes committed by prisoners of war involves ensuring the efficiency of criminal proceedings, the mandatory participation of a lawyer, informing about the progress of the pre-trial investigation in general, and ensuring qualified protection in particular of the protecting power, compliance with the procedure for notifying a prisoner of war of suspicion, detention, and application of preventive measures.
The main ways of implementing the protection function have been defined: mandatory involvement of a defender; use of procedural opportunities to collect evidence and build your line of defence; participation in procedural actions; making comments and objections during certain procedural actions; obtaining access to the materials of criminal proceedings, the ability to make copies of them or their reflection; appeal against decisions, actions, or inaction of a pre-trial investigation body, prosecutor, investigating judge; awareness of the progress of the pre-trial investigation, etc.
It has been substantiated that war crimes are distinguished by a number of special features that directly affect the process of their pre-trial investigation. The main such features are the definition of jurisdiction, the subject of proof, the specifics of the application of measures to ensure criminal proceedings, etc. It has been established that the features of the pre-trial investigation of war crimes under martial law correlate with the mechanism for implementing the function of protection during the investigation of the criminal offences under study.
It has been established that the implementation of the defence function during the pre-trial investigation of war crimes under martial law is to ensure the suspect's right to defense. It has been noted that this function can be implemented by the suspect directly and/or indirectly. It has been established that the most effective way to implement the function of defence in this category of proceedings is a synergistic combination of the suspect's personal participation in criminal proceedings and the use of legal assistance from a lawyer. It has been emphasised that it is important to establish close contact between the suspect and the defender, which, in turn, will allow choosing a single line of conduct when developing defence tactics.
