Sons of the ATF liberty folks from Ruby Ridge and Waco.
All they had to do was show cause in a letter or peaceful in-person interview WHY they believed he was in the business of selling firearms like an FFL but didn’t have one.
If it is legal to sell guns privately at a gun show, then they should have proved their contention before murdering the man.
Just like RR and WACO, the ATF had multiple opportunities to act nonviolently. But they chose not to. Murderers. Lon Horiuchi would be proud of them.
The ATF didn't perform a 10 vehicle no-knock pre-dawn raid because Malinowski was dangerous, they did it (just like Waco and Ruby Ridge) to SEND A MESSAGE TO OTHERS.