33 U.S. Code § 920 - Presumptions
PresumptionsIn any proceeding for the enforcement of a claim for compensation under this chapter it shall be presumed, in the absence of substantial evidence to the contrary—
That the injury was not occasioned by the willful intention of the injured employee to injure or kill himself or another.
(Mar. 4, 1927, ch. 509, § 20, 44 Stat. 1436.)