The testimony of a witness may be taken by deposition, upon application by a participant in a proceeding pending before the agency, before the hearing is closed, upon approval by the agency head or the presiding officer.
1 Pa. Code § 35.145
This section cited in 1 Pa. Code § 35.137 (relating to oral examination); 4 Pa. Code §89.31 (relating to investigation); 4 Pa. Code §265.3 (relating to level II hearings); 4 Pa. Code §607a.13 (relating to subpoenas); 7 Pa. Code §179.16 (relating to limited discovery); 25 Pa. Code §1021.102 (relating to discovery); 34 Pa. Code §95.94 (relating to depositions); 34 Pa. Code §131.62 (relating to oral depositions); 34 Pa. Code §131.63 (relating to time for taking oral depositions); 34 Pa. Code §131.64 (relating to notice of oral depositions); 34 Pa. Code §131.65 (relating to objections to taking of oral depositions); 34 Pa. Code §131.68 (relating to discovery of records); 34 Pa. Code §131.70 (relating to discovery of statements of parties or witnesses); 34 Pa. Code §131.204 (relating to UEGF subpoenas and interrogatories); 40 Pa. Code §15.49 (relating to deposition); 40 Pa. Code §17.6 (relating to depositions and discovery); 51 Pa. Code §21.5 (relating to conduct of investigations); 52 Pa. Code §5.321 (relating to scope); 52 Pa. Code §5.343 (relating to procedures in deposition by oral examination); 52 Pa. Code §1005.162 (relating to depositions); 55 Pa. Code §41.120 (relating to limitations on scope of discovery); and 58 Pa. Code §493a.11 (relating discovery).