As I understand it, Peter Strzok is to appear to day before the House Judiciary Committee and House Oversight and Government Reform Committee to provide sworn testimony. Link here Press reports have indicated that he had voluntarily agreed to provide this testimony in a open session. However the House Committees chose to issue a subpoena, forcing him to testify in closed session.link here
As a witness, who has agreed to testify in open session, is he precluded or subject to punishment for publicly disclosing any of HIS statements in the "closed door session" today. (Assuming that he does not publicly disclose any of the members or investigators statements or questions)
Obviously he should not disclose any classified information.
More generally, if a witness is subject to sanction under these circumstances, is issuing a subpoena a useful tactic to silence a witness who otherwise is willing to be public with unclassified information?