Interesting story. This guy was actually airport director at the airport in Little Rock, AR. He used to buy and sell a bunch of guns and was an avid collector. He was killed when ATF agents raided his home and he responded with gunfire. The controversy seems to circle around the fact that:

* the ATF decided not to raid his home when he was out of town but early in the morning when he was at home

* the ATF gave him 28 seconds to comply with their announcement after which they battered the door down

Given the fact that the agents weren't wearing body cameras, the guy had a normal day job that he'd go to, and that 28 seconds is certainly too short to dispose of firearms it does seem a lot like execution served by way of search warrant. Certainly, I wouldn't be able to let anyone in 28 s after waking up to pounding on my door.