The commission shall investigate all accidents that may occur upon the lines of any common carrier resulting in loss of life, to any passenger or employee, and may investigate any and all accidents or wrecks occurring on the line of any common carrier. Notice of the investigation shall be given in all cases for a sufficient length of time to enable the company affected to participate in the hearing and may be given orally or in writing, in such manner as the commission may prescribe.

Such witnesses may be examined as the commission deems necessary and proper to thoroughly ascertain the cause of the accident or wreck and fix the responsibility therefor. The examination and investigation may be conducted by an inspector or deputy inspector, and he or she may administer oaths, issue subpoenas, and compel the attendance of witnesses, and when the examination is conducted by an inspector or deputy inspector, he or she shall make a full and complete report thereof to the commission.