Warrants of pardon and commutation shall be issued in triplicate, one to be given to the convict, one to be filed with the clerk of the court of common pleas in whose office the sentence is recorded, and one to be filed with the head of the institution in which the convict was confined, in case he was confined.
All warrants of pardon, whether conditional or otherwise, shall be recorded by said clerk and the officer of the institution with whom such warrants and copies are filed, in a book provided for that purpose, which record shall include the indorsements on such warrants. A copy of such a warrant with all indorsements, certified by said clerk under seal, shall be received in evidence as proof of the facts set forth in such copy with indorsements.