TITLE II
CHAPTER I
INTERNATIONAL LETTERS ROGATORY FROM ABROAD
Art. 20
(Appearance of witnesses and experts)
1. Without prejudice to contrary provisions contained in the bilateral agreements in force for the Republic of San Marino, a witness or expert who has failed to answer a summons to appear, service of which has been requested, shall not be subjected to any punishment or measure of restraint, unless subsequently he voluntarily enters the territory of the requesting State and is there again duly summoned.
Art. 21
(Refunding of expenses for witnesses or experts)
1. With the exception of different criteria contained in the bilateral conventions in force for the Republic of San Marino, the allowances to be paid and the travelling and subsistence expenses to be refunded to a witness or expert by the requesting State shall be calculated as from his place of residence and shall be at rates at least equal to those provided for in the scales and rules in force in the country where the hearing is intended to take place.
Art. 22
(Immunity of witnesses or experts)
1. No witnesses or experts, whatever their nationality, appearing before the judicial authorities of the requesting State in response to a summons, shall be prosecuted or detained or subjected to any other restriction of their personal liberty in the territory of the requesting State for acts or convictions anterior to their departure from the territory of the Republic of San Marino.
2. The immunity provided for in this Article shall cease when the witness or expert, having had the opportunity to leave the territory of the requesting State during a period of fifteen days from the date on which his presence is no longer required by the judicial authorities, has nevertheless remained in the territory, or having left it, has voluntarily returned.
Facilitating voluntary appearance of persons - national procedures for ICC proceedings
EDIT.