It's very easy to discern. The former will be found with only foodstuffs and first aid items in their possession and will generally be accompanied by their children or infirm family members.
The latter will be found with expensive footwear, jewelry, electronics and liquor, traveling in wolfpacks comprised almost entirely of able-bodied men who are doing nothing to help fellow citizens.
It should take about one-half of one second to see the difference.
Never said you can't tell the difference, I said you can't yet discern what the percentage of thugs is as opposed to good folks trying to stay alive. This means we can't blanketly label everyone as filthy "looters" and ask they be shot on site. Some of them are stealing other 'things' to barter with for food and water. The Cheif of Police, Eddie Compass, said even his own officers were breaking into stores to get food, water and supplies. The people are up to their necks in water and chaos, they see their own police 'looting' and they're supposed sit around and have a love-in?
This isn't a typical flooded city like we've seen so many times on the news, it's a disaster of unequalled proportions in American history. And who's to say that some of the people stealing guns aren't doing it defend their own lives or the lives of their families? Nobody else was there to defend them.