If you are driving a vehicle yes, you must also give proof of your identity.  If you are not driving then law enforcement must have reasonable suspicion that you committed a crime. Let’s look a the two main statutes: A.R.S. 28-1595 states that a person operating a motor vehicle must provide their driver’s license or other proof of identification if they do not have a license. Failure to do so is a class 2 misdemeanor. This same statute requires anyone who is a passenger in the vehicle and who law enforcement has a reasonable cause to believe committed a crime also must provide evidence of the person’s identity. A.R.S. 13-2412 states that any person lawfully detained based on reasonable suspicion that the person committed a crime must state their true full name. To violate this statute the officer must also first inform you that refusal to answer is unlawful. Whether or not an officer has reasonable suspicion will ultimately be up to the judge. Whether it’s through a motion to suppress or motion for egregious government conduct the judge will determine after your attorney has had an opportunity to cross examine. If you are not ultimately charged with a crime you could also bring a civil lawsuit against the officer where the judge will decide if the officer did in fact have reasonable suspicion.