PHOENIX (AP) -- A federal judge ruled Wednesday that Arizona authorities can enforce the most contentious section of the state's immigration law, which critics have dubbed the "show me your papers" provision.
The ruling by U.S. District Judge Susan Bolton clears the way for police to carry out the 2010 law's requirement that officers, while enforcing other laws, question the immigration status of those they suspect are in the country illegally.
The requirement has been at the center of a two-year legal battle that culminated in a U.S. Supreme Court decision in June upholding the requirement.
Opponents then asked Bolton to block the requirement, arguing that it would lead to systematic racial profiling and unreasonably long detentions of Latinos if it's enforced.
Lawyers for Arizona Gov. Jan Brewer urged the judge to let the requirement go into effect, saying the law's opponents were merely speculating in their racial profiling claims, that police have received training to avoid discriminatory practices and that officers must have "reasonable suspicion" that a person is in the country illegally to trigger the requirement.
Less controversial sections of the law have been in effect since late July 2010, but rarely been used.
Arizona's law was passed in 2010 amid voter frustration with the state's role as the busiest illegal entry point into the country. Five states -- Alabama, Georgia, Indiana, South Carolina and Utah -- have adopted variations on Arizona's law.
Brewer's office says the law is expected to go into effect shortly.