@hopfgeist
It seems to be a legal term.
From Wikipedia
»… the presumption that the moving vessel is at fault, stating that "presumption derives from the common-sense observation that moving vessels do not usually collide with stationary objects unless the [moving] vessel is mishandled in some way"«
But in this case, there seemed to be lots of lights on the Key Bridge, and possibly enuf ambient light to see it even without them.
The whole thing seems odd, so odd that lots of organizations and people felt the need to point it out that it seems to be accident, no deliberate act.