To clarify, I'm not sure if he would or would not have a CAC card due to being AWOL. If he simply deserted, I guess he'd still have one and it'd at least look proper as long as it wasn't expired. I agree with the other poster that if he was AWOL, he probably didn't present a military ID.
Also, the checkpoint guards don't just look at IDs, they can also scan them. I don't know the procedures used for active-duty personnel. As a civilian contractor (in a personal vehicle dressed in civilian clothes,) my CAC card is usually scanned by a hand-held scanner. Like a drivers' license, these cards have barcodes that can be read - this is to prevent a scenario where a contractor is fired/banned/etc. but still has a valid card from gaining access to an installation.
It is interesting that the reports say the driver had a 'fradulent' ID. Not expired or invalid, but fraudulent. To me, this suggests that this was certainly a planned incident and that there may be others involved in the planning...
Thanks for your clarification. It came to mind, could 'fraudulent' mean he presented his military ID, which then turned up his AWOL status? That term would imply something more sinister, but could it be misapplied in this case to mean an ID that was flagged as AWOL?
Frankly, this is all speculation, and we'll know more (hopefully) once they end their investigation. Then again, we may not be told...