The State Mine Inspector shall make a personal investigation as to the nature and cause of all serious accidents in mines under his supervision. He shall make a record of the circumstances attending the accident, as developed at the coroner's inquest and by his own personal investigation. A copy of the record shall be filed with the Department within 30 days following the conclusion of the investigation, and the report shall thereupon become a part of the records of the Department. To enable the State Mine Inspector to make his investigation he has the power to compel the attendance of witnesses, and to administer oaths or affirmations to them.
225 ILCS 705/10.04