16 Pa.C.S. § 14321: Designation, powers and duties of first assistant.

The following shall apply:

(1) If more than one assistant district attorney is appointed, the district attorney shall designate one assistant as the first assistant.

(2) The first assistant or the assistant district attorney if only one is appointed shall, in the absence of the district attorney from the jurisdiction or during the district attorney's inability to perform the duties of the office through sickness or other cause, be vested with all the duties, powers and privileges given by law to the district attorney and generally shall be empowered to do and perform all things in connection with the office that the district attorney is authorized to do or perform.

(3) In case of an incapacity of the district attorney or the first assistant, or both, a duty, power or privilege may be exercised by other assistant district attorneys, if any, as may be designated by the district attorney.