And legally stops them because...
Hibble vs. Nevada - USSC
You must give your name when asked but do not need to produce documents. Further, if not being stopped for cause, providing any info may be in question...
The decision stems from the case of Larry Hiibel, who was arrested in May 2000 after he refused a deputy sheriff’s repeated demand that he produce some form of identification.
The encounter took place at the side of a road in Humboldt County, Nev. The deputy had received a report of a man striking a woman in a pickup truck. When the deputy arrived at the scene, Mr. Hiibel was standing outside a pickup truck that was parked on the shoulder of the road. His daughter was sitting inside the truck.
The deputy asked Hiibel 11 times to produce identification. Hiibel repeatedly refused, saying he’d done nothing wrong. The deputy placed him under arrest in accord with a Nevada law that permits police to detain criminal suspects for up to 60 minutes to compel them to identify themselves.
Hiibel refused to comply. He was charged and convicted of violating the mandatory identity law, a misdemeanor punishable by up to six months in jail. His conviction was affirmed by a state appeals court and the Nevada Supreme Court.
In upholding his conviction and the mandatory identity-disclosure law, the majority justices also said the law only requires that a suspect disclose his or her name, rather than requiring the production of a driver’s license or another document.