I think the point is that of course, if he was drunk it may have contributed to his reaction, but that doesn’t make it the ~cause~ of the crash. It’s also possible that a sober driver could have done just the same thing. That’s a fact that has to be sorted out by a jury.
Of course if he was DUI, he should be punished for that, apart from whatever fallout there is from the crash.
Say some drunk driver is sitting at a red light and gets rear-ended at high speed— knocking his car into a pedestrian in the crosswalk. Does the DUI make it his fault there too? No...
No. But he was breaking the law by driving drunk regardless of any ill or good effects of his foray. Should the driver in the real accident and the one in your hypothetical be excused/busted because they were/were not drunk?
The answer is "no". Drunk driving is a crime, whether the drunk is snoring in an idling car at a commuter lot or plowing into a motorcycle group at speed.
Your serve.
It would be like me being drunk, and someone rear ending me, at 5MPH at a red light....And since I am drunk, my foot hits the gas, instead of reacting properly and hitting the brake, causing me to drive into the intersection, broadsiding a car full of cub scouts, killing them all.