California Code, Government Code - GOV § 3613

The board of investigation shall be composed of no more than five members, one of whom shall be designated by the Governor as chairperson.  Members of the board shall receive one hundred dollars ($100) for each day actually spent by them in the work of the board and shall receive their actual and necessary expenses incurred in the performance of their duties.

The board may hold public hearings to ascertain the facts with respect to the causes and circumstances of the dispute.  For the purpose of any hearing or investigation, the board may summon and subpoena witnesses, require the production of papers, books, accounts, reports, documents, records, and papers of any kind and description, to issue subpoenas, and to take all necessary means to compel the attendance of witnesses and procure testimony.