All documents, papers and records in the office of the county board of elections of each county shall be preserved therein for a period of at least eleven (11) months, and all official ballots and the contents of ballot boxes shall be preserved therein for a period of at least four (4) months; in the event the county board has been notified in writing by the district attorney of the county, or by a judge of a court of record, to preserve said papers or contents of ballot boxes for a longer period of time, for the purposes of pending prosecution or litigation, said records shall be preserved accordingly.
25 P.S.§ 2649