; quorum; vacancies (1) In general After its initial meeting, the Commission shall meet upon the call of the co-chairs of the Commission. (2) Quorum Nine members of the Commission shall constitute a quorum for purposes of conducting business, except that 2 members of the Commission shall constitute a quorum for purposes of receiving testimony. (3) Vacancies Any vacancy in the Commission shall not affect its powers, but shall be filled in the same manner in which the original appointment was made. (4) Quorum with vacancies If vacancies in the Commission occur on any day after 90 days after the date of the enactment of this Act, a quorum shall consist of a majority of the members of the Commission as of such day. (e) Duties The duties of the Commission are as follows: (1) To review the effectiveness of the current implementation of the Foreign Intelligence Surveillance Act of 1978 ( 50 U.S.C. 1801 et seq. ). (2) To develop recommendations for legislative action to reform the Foreign Intelligence Surveillance Act of 1978 ( 50 U.S.C. 1801 et seq. ) that provide for the effective conduct of United States intelligence activities and the protection of privacy and civil liberties. (f) Powers of Commission (1) In general (A) Hearings The Commission or, on the authorization of the Commission, any subcommittee or member thereof, may, for the purpose of carrying out this section— (i) hold such hearings and sit and act at such times and places, take such testimony, receive such evidence, and administer such oaths; and (ii) require, by subpoena or otherwise, the attendance and testimony of such witnesses and the production of such books, records, correspondence, memoranda, papers, and documents, as the Commission or such designated subcommittee or designated member considers necessary. (B) Issuance and enforcement of subpoenas (i) Issuance A subpoena issued under subparagraph (A)(ii) shall— (I) bear the signature of the co-chairs of the Commission