25 Pa. Stat. § 3404
The court of common pleas to which a petition shall be presented as aforesaid, contesting the right of a candidate for senator or representative in the General Assembly to the nomination or to the seat for which he may have been returned as elected, or contesting the right of a candidate for representative in Congress to the nomination, shall have authority to subpoena and to compel the attendance of any officer of the primary or election complained of, and of any person capable of testifying concerning the same, and also to compel the production of all books, papers, tally lists, ballots, ballot boxes, voting machines and all documents which may be required at such hearing, in like manner, and to the same extent as in other cases litigated before such court; to take testimony and to proceed without delay, postponing for the purpose, if necessary, all other business, to the hearing and determination of such contest.
25 P.S. § 3404