yes, lets try this again. where exactly does the court say that? please reference the actual case, and not someones misinterpretation of it.
the court doesn't say:"the questioning of the immigration status didn't violate of the 4th amendment because it was not an independent seizure", what it does say: "Because Mena’s initial detention was lawful "(they had a warrant to search the property) "and the NinthCircuit did not hold that the detention was prolonged by thequestioning," (the questioning did not extend beyong the time it took to conduct the search) "there was no additional seizure within the meaningof the FourthAmendment, and, therefore, no additional Fourth Amendmentjustification for inquiring about Mena’s immigrationstatus was required."