It appears that the men were horsing around when one pushed another man into the water — not realizing that he could not swim. It appears that each of the men ended up in the water trying to help but ultimately drowned. The victims are listed as 57-year-old Darrel Shappart, 26-year-old Jared Hale, his 30-year-old brother Aaron Hale and 30-year-old Stephan Verbeck.
While there were life jackets on board, none of the men were wearing them.
Source: here
