Part VI
Mutual legal assistance in criminal matters
CHAPTER III
Special forms of international assistance
Article 157
Safe conduct
1. Any person appearing on the territory of a foreign State under the terms and for the purposes of the provisions of Articles 154, 155 or 156 above:
a) shall not be arrested, prosecuted, punished or subjected to any other restriction of his personal liberty in respect of any act anterior to his departure from the Portuguese territory other than those mentioned in the request for co-operation;
EDIT.