To put it another way, it is not unreasonable to think that this would have ended very differently if the Costco employee had called the police and said "We have a man in our store who claims he has a concealed handgun license but we're not sure. Could you send somebody over to verify it?" I don't underestimate the ability of police to botch that up as well, but it would have likely produced a much less tense situation than "there's a guy with a gun going berserk in our store!"
Nobody, not the police or any of the news stories I've read, use the that description. The common account seems to be that the Costco employee told police that there was someone in the store destroying merchandise and he was armed. A witness account says that the victim had been breaking up a pack of energy drinks and seeing how many he could fit into a backpack. So maybe 'destroying merchandise' may have been a stretch but he was acting improperly, and it's a far cry from claiming he told police he was 'going berserk'. In fact it was the police who used that term to describe the victims actions once they accosted him outside the store. Nothing the Costco employee seems to have done caused panic in the store; there are no accounts from anyone of a mad rush to the door or unruly evacuation or anything. So police knew that there was someone causing a disruption and he was armed. Nothing inaccurate in that. Everything they did after that seems to have been an unnecessary escalation of the situation ending in the shooting of a man who shouldn't have been shot. Costco can't be blamed for that.
This is a post much earlier in the thread. I just wanted to highlight it to point out that there really ought to be a change in the protocol for notifying the police about "a man with a gun." The dispatcher should be required to give more information than that, preferably details of what was seen and why their attention is needed.
Maybe somebody else has pointed this out.