More likely the occupants were fugitives, and knew that this would be uncovered the moment they had to produce ID.
Or, it was a car-jacking/hostage situation. We just had that here in Jacksonville a couple of days ago. An officer was shot in the chin when a bank robber had car-jacked an innocent person to be his get-away. It was assumed the car-jacking victim was in on the robbery. It was only learned after a crash and then shootout that they learned the driver was a victim.
BTW, the perp was killed.
http://jacksonville.com/news/public-safety/2017-07-26/suspect-who-shot-jacksonville-officer-being-killed-couldn-t-escape