A public prosecutor or other governmental lawyer shall not, without prior judicial approval, subpoena an attorney to appear before a grand jury or other tribunal investigating criminal activity in circumstances where the prosecutor or other governmental lawyer seeks to compel the attorney/witness to provide evidence concerning a person who is or has been represented by the attorney/witness.
Pa. R. Prof. Cond. 3.10
Comment:
[1] It is intended that the required "prior judicial approval" will normally be withheld unless, after a hearing conducted with due regard for the need for appropriate secrecy, the court finds (1) the information sought is not protected from disclosure by Rule 1.6, the attorney-client privilege or the work product doctrine; (2) the evidence sought is relevant to the proceeding; (3) compliance with the subpoena would not be unreasonable or oppressive; (4) the purpose of the subpoena is not primarily to harass the attorney/witness or his or her client; and (5) there is no other feasible alternative to obtain the information sought.
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