1 hour ago, chickenslegs said:

It's possible that the logging driver made a quick decision to avoid the tanker and chose to hit the container instead.

 

Who knows what the tanker was carrying, but chances are good that it was something very nasty.

Chickenslegs, that makes sense. After some pondering, I thought perhaps that once he realized his escape route was cut of by the tanker, he chose hitting the first lorry on an angle to lessen what would have been a straight-in impact on the tanker. But your idea that he’d be afraid of the tanker’s contents sounds right.

A normal following distance is usually summed up by the two-second rule.  This should give the driver enough time to stop if the vehicle ahead does the same thing.  For a commercial vehicle, however, the rule is doubled, i.e. a four-second rule.  In the case of this video, the log truck had at least six seconds from the time the other truck pulled across the lanes to the time of impact.  As others have noted, no brake lights appeared for most of that.  Regardless of how the log truck driver thought he could swerve around through the shoulder of the road, it was unwise not to slow down considerably upon seeing the lanes blocked.  My assessment would be, from a legal perspective, 100% fault of the log truck driver, who could have stopped safely, although the other trucks' drivers lacked etiquette and were equally rude and selfish in their driving.  Their selfishness contributed to the accident, even if their actions were technically legal.

 

Of interest to the case might be the fact that the log truck driver had just used his hazard lights, in place of a right-turn signal, to change lanes from the left lane to the right lane, before the other truck had pulled out and while the road was entirely clear of moving vehicles ahead of him.  This brings up several questions more, such as: Was he intending to do a U-turn at that intersection?  Was he simply trying to avoid passing the truck on the shoulder ahead in such close proximity?  If the latter, and he had demonstrated awareness of the situation, why are there no indicators of braking when that truck pulls out ahead of him?  If it truly was "brake failure," his brake lights were obviously as non-functional as the brakes themselves.