he or she was transferred for time spent in the custody of the State Party to which he or she was transferred. 12. Unless the State Party from which a person is to be transferred in accordance with paragraphs 10 and 11 of this Article so agrees, that person, whatever his or her nationality, shall not be prosecuted, detained, punished or subjected to any other restriction of his or her personal liberty in the territory of the State to which that person is transferred in respect of acts, omissions or convictions prior to his or her departure from the territory of the State from which he or she was transferred. 13. Each State Party shall designate a central authority that shall have the responsibility and power to receive requests for mutual legal assistance and either to execute them or to transmit them to the competent authorities for execution. Where a State Party has a special region or territory with a separate system of mutual legal assistance, it may designate a distinct central authority that shall have the same function for that region or territory. Central authorities shall ensure the speedy and proper execution or transmission of the requests received. Where the central authority transmits the request to a competent authority for execution, it shall encourage the speedy and proper execution of the request by the competent authority. The Secretary-General of the United Nations shall be notified of the central authority designated for this purpose at the time each State Party deposits its instrument of ratification, acceptance or approval of or accession to this Convention. Requests for mutual legal assistance and any communication related thereto shall be transmitted to the central authorities designated by the States Parties. This requirement shall be without prejudice to the right of a State Party to require that such requests and communications be addressed to it through diplomatic channels and, in urgent circumstances, where the States Parties agree, through the International Criminal Police Organisation, if possible. 14. Requests shall be made in writing or, where possible, by any means capable of producing a written record, in a language acceptable to the requested State Party, under conditions allowing that State Party to establish authenticity. The Secretary-General of the United Nations shall be notified of the language or languages acceptable to each State Party at the time it deposits its instrument of ratification, acceptance or approval of or accession to this Convention. In urgent circumstances and where agreed by the States Parties, requests may be made orally, but shall be confirmed in writing forthwith. 15. A request for mutual legal assistance shall contain: (a) the identity of the authority making the request; (b) the subject matter and nature of the investigation, prosecution or judicial proceeding to which the request relates and the name and functions of the authority conducting the investigation, prosecution or judicial proceeding; (c) a summary of the relevant facts, except in relation to requests for the purpose of service of judicial documents; (d) a description of the assistance sought and details of any particular procedure that the requesting State Party wishes to be followed; (e) where possible, the identity, location and nationality of any person concerned; and (f) the purpose for which the evidence, information or action is sought. 16. The requested State Party may request additional information when it appears necessary for the execution of the request in accordance with its domestic law or when it can facilitate such execution. 17. A request shall be executed in accordance with the domestic law of the requested State Party and, to the extent not contrary to the domestic law of the requested State Party and where possible, in accordance with the procedures specified in the request. 18. Wherever possible and consistent with fundamental principles of domestic law, when an individual is in the territory of a State Party and has to be heard as a witness or expert by the judicial authorities of another State Party, the first State Party may, at the request of the other, permit the hearing to take place by video conference if it is not possible or desirable for the individual in question to appear in person in the territory of the requesting State Party. States Parties may agree that the hearing shall be conducted by a judicial authority of the requesting State Party and attended by a judicial authority of the requested State Party. 19. The requesting State Party shall not transmit or use information or evidence furnished by the requested State Party for investigations, prosecutions or judicial proceedings other than those stated in the request without the prior consent of the requested State Party. Nothing in this paragraph shall prevent the requesting State Party from disclosing in its proceedings information or evidence that is exculpatory to an accused person. In the latter case, the requesting State Party shall notify the requested State Party prior to the disclosure and, if so requested, consult with the requested State Party. If, in an exceptional case, advance notice is not possible, the requesting State Party shall inform the requested State Party of the disclosure without delay. 20. The requesting State Party may require that the requested State Party keep confidential the fact and substance of the request, except to the extent necessary to execute the request. If the requested State