I would agree that if a gun dealer sells a gun to someone they were clearly aware would be a danger (although I would think that would be difficult to prove, and a very slippery slope for gun dealers), there could and should be some liability concerns for them. Although I didn't see any indication that was the case here from the article, only the question of whether it would apply if it was the case.

Seems to me we should be focusing our efforts much more on improving and strengthening the background check system, more so than trying to pin liability on dealers and manufacturers for the failings of that system.