(KCEN) -- Arizona police can now question a person's immigration status during routine traffic stops.
It started yesterday after a federal judge upheld the Show Me Your Papers provision of the state's new immigration law earlier this month.
The law requires officers to question the immigration status of those they suspect are in the country illegally.
Opponents say it will lead to racial profiling.
Supporters of the law say police have received training to avoid discriminatory practices.