The Arizona law would only allow that if he was stopped for another reason and there were additional reasons to suspect that there was a problem with documentation - such as a refusal to show a driver’s license or suspicious behavior.
So it sounds like the Arizona law would be a step up from what this person experiences now. Why do you think Obama’s DOJ doesn’t want to improve the situation for this friend of yours?
Do you really think the police can't make up a plausible reason for stopping someone if they want to?
Why do you think Obama’s DOJ doesn’t want to improve the situation for this friend of yours?
For the same reason you started beating your husband - in other words, the question is a logical fallacy.