“Committee,” as used in this chapter, except when more particularly provided in this chapter, includes:
(1) A committee appointed by either the house of representatives or the senate;
(2) A committee appointed by the joint action of such bodies;
(3) A committee appointed by the speaker of the house of representatives or the speaker of the senate or a joint committee appointed by both speakers in accordance with the rules of proceedings adopted by the respective houses; and
(4) Any subcommittee designated out of the membership of any such committee; when any such committee or subcommittee thereof is charged with any duty to make investigation and report, to or for the benefit of either or both houses, in respect of any matter or thing referred to any such committee.