Section 850.30 - Procedures for Coast Guard investigation(a) The Coast Guard conducts an investigation under § 850.25 using the procedures in 46 CFR 4.0 1 - 1 through 4.23-1.(b) The Board may designate a person or persons to participate in every phase of an investigation, including on-scene investigation, that is conducted under the provisions of § 850.25 .(c) Consistent with Coast Guard responsibility to direct the course of the investigation, the person or persons designated by the Board under paragraph (b) of this section may:(1) Make recommendations about the scope of the investigation.(2) Call and examine witnesses.(3) Submit or request additional evidence.(d) The Commandant provides a record of the proceedings to the Board of an investigation of a major marine casualty under paragraph (a) of this section.(e) The Board, under the Act, makes its determination of the facts, conditions, and circumstances, and the cause or probable cause of a major marine casualty, using the record of the proceedings provided by the Commandant under paragraph (d) of this section and any additional evidence the Board may acquire under its own authority.(f) An investigation by the Coast Guard under this section is both an investigation under the Act and under R.S. 4450 ( 46 U.S.C. 239 ).