For any lawful contact stop, detention or arrest made by a law enforcement official or a law enforcement agency of this state or a law enforcement official or a law enforcement agency of a county, city, town or other political subdivision of this state in the enforcement of any other law or ordinance of a county, city or town or this state where reasonable suspicion exists that the person is an alien who and is unlawfully present in the United States,
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in other words, you are stopped at a sobriety checkpoint (lawful stop), you say: "good evening officer" -in your thick Russian accent- thus giving the police officer reasonable suspicion to haul you in for questioning.

here - I found something very relevant..
Muehler v. Mena, 544 U.S. 93 (2005), was a unanimous decision by the United States Supreme Court, which held that the Fourth Amendment to the United States Constitution allows
1. detention of a search subject in handcuffs while a search is being conducted,
2. and that it does not require officers to have an independent reasonable suspicion before questioning a subject about their immigration status.
and the Arizona law DOES require the cops to have reasonable suspicion.. so if anything, it's stricter than the federal law..

Respondent Mena and others were detained in handcuffs during a search of the premises they occupied. Petitioners were lead members of a police detachment executing a search warrant of these premises for, inter alia, deadly weapons and evidence of gang membership.

Fourth Amendment to the United States Constitution allows
1. detention of a search subject in handcuffs while a search is being conducted,
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Mena’s detention in handcuffs for the length of the search did not violate the Fourth Amendment. That detention is consistent with Michigan v. Summers, 452 U.S. 692, 705, in which the Court held that officers executing a search warrant for contraband have the authority “to detain the occupants of the premises while a proper search is conducted.” The Court there noted that minimizing the risk of harm to officers is a substantial justification for detaining an occupant during a search,

2. and that it does not require officers to have an independent reasonable suspicion before questioning a subject about their immigration status.
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Because Mena’s initial detention was lawful and the Ninth Circuit did not hold that the detention was prolonged by the questioning

the legality of questioning someone's immigration status was in the court decision regardless of the circumstances.. and that's what the Court concluded -

***********.law.cornell.edu/supct/html/03-1423.ZS.html

2. Theofficers’ questioning of Mena about her immigration statusduring her detention did not violate her Fourth Amendmentrights. The Ninth Circuit’s holding to the contraryappears premised on the assumption that the officers wererequired to have independent reasonable suspicion in order toso question Mena. However, this Court has “heldrepeatedly that mere police questioning does not constitute aseizure.” Florida v. Bostick, 501 U.S. 429, 434. Because Mena’s initial detention was lawful and the NinthCircuit did not hold that the detention was prolonged by thequestioning, there was no additional seizure within the meaningof the FourthAmendment, and, therefore, no additional Fourth Amendmentjustification for inquiring about Mena’s immigrationstatus was required. Cf. Illinois v. Caballes,543 U.S. ___ , ___ (slip op., at 2—4). Pp. 7—8.

the legality of questioning someone's immigration status was in the court decision regardless of the circumstances..
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stop interpreting the law. "Because Mena’s initial detention was lawful and the NinthCircuit didnot hold that the detention was prolonged by thequestioning,"

"officers executing a search warrantfor contraband have the authority “to detain the occupants of thepremises while a proper search is conducted.”
meaning they couldn't have detained them withpout a warrant.
and only "Because Mena’s initial detention waslawful and the Ninth Circuit did not hold that the detention wasprolonged by the questioning there was no additional seizure within the meaning of the Fourth Amendment, and, therefore, no additional Fourth Amendment justification for inquiring about Mena’s immigration status was required."

3. Because the Ninth Circuit did not address Mena’s alternative argument that her detention extended beyond the time the police completed the tasks incident to the search, this Court declines to address it.
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that actually might have been a violation of Mena's Fourth Amendment rights, but since it was never addressed by the Ninth Circuit Court, the Supreme Court declined to address it as well.

and nowhere does is state: "regardless of the circumstances."
if anything, there had to be a warrant, the suspects had to be legally detained, and their detention (including the questions concerning their immigration starus) shouldn't have extended beyond the time it took to search the premises - although it did in this case.