§ 60. Testimony before legislative committees. A legislative committee may require the attendance of witnesses in this state whom the committee may wish to examine, or may issue a commission for the examination of witnesses who are out of the state or unable to attend the committee or excused from attendance, which commission if directed by the house or legislature by which the committee is appointed may be executed during the recess of the legislature. A commission issued as provided by this section shall be in the form used in the courts of record of this state and shall be executed in like manner. Unless otherwise instructed by the committee appointing them the commissioners shall examine privately every witness attending before them and shall not make public the particulars of such examination. No committee of either house or a joint committee of both houses shall have the power to take testimony at a private hearing or at a public hearing unless at least two of its members are present at such hearing.