§ 118. Technical rules of evidence or procedure not required. The
chairman or board in making an investigation or inquiry or conducting a
hearing shall not be bound by common law or statutory rules of evidence
or by technical or formal rules of procedure, except as provided by this
chapter; but may make such investigation or inquiry or conduct such
hearing in such manner as to ascertain the substantial rights of the
parties. Declarations of a deceased employee concerning the accident
shall be received in evidence and shall, if corroborated by
circumstances or other evidence, be sufficient to establish the accident
and the injury.