From the video it looks bad for the guy speficically for the time it took him to get the second weapon. That shows coherent thought. and that, in the law, is murder.
In so far as it goes, yes. It may be inconclusive.
Ersland is disabled; he wears a back-brace. I doubt he's capable of moving other than slowly. Coherent though does not mean murder if the shootee is still posing a threat. Which, again, is the point of contention.
I think some folks here are just 'way too quick to condemn the man.