4. The provisions of this article shall also apply to victims insofar as they are witnesses. Article 25. Assistance to and protection of victims 1. Each State Party shall take appropriate measures within its means to provide assistance and protection to victims of offences covered by this Convention, in particular in cases of threat of retaliation or intimidation. 2. Each State Party shall establish appropriate procedures to provide access to compensation and restitution for victims of offences covered by this Convention. 3. Each State Party shall, subject to its domestic law, enable views and concerns of victims to be presented and considered at appropriate stages of criminal proceedings against offenders in a manner not prejudicial to the rights of the defence. Article 26. Measures to enhance cooperation with law enforcement authorities 1. Each State Party shall take appropriate measures to encourage persons who participate or who have participated in organized criminal groups: (a) To supply information useful to competent authorities for investigative and evidentiary purposes on such matters as: (i) The identity, nature, composition, structure, location or activities of organized criminal groups; (ii) Links, including international links, with other organized criminal groups; (iii) Offences that organized criminal groups have committed or may commit; (b) To provide factual, concrete help to competent authorities that may contribute to depriving organized criminal groups of their resources or of the proceeds of crime. 2. Each State Party shall consider providing for the possibility, in appropriate cases, of mitigating punishment of an accused person who provides substantial cooperation in the investigation or prosecution of an offence covered by this Convention. 3. Each State Party shall consider providing for the possibility, in accordance with fundamental principles of its domestic law, of granting immunity 28