The full impact of the state's new immigration enforcement law may not be clear for months - attorneys and law enforcement officials need to make sense of its language, and legal challenges will be settled in court.
But here are seven things we do know about SB 1070, which Gov. Jan Brewer signed into law April 23 and is scheduled to go into effect in mid-August:
1. It requires police officers to determine the immigration status of everybody they arrest before that person is released.
• The law says: "Any person who is arrested shall have the person's immigration status determined before the person is released. The person's immigration status shall be verified with the federal government pursuant to 8 United States code section 1373(c)."
• What that means: This could mean lots of extra work for local police officers, who have to make the initial determination and then contact federal agents for verification, said Raymond Michalowski, an Arizona regents professor of criminology at Northern Arizona University. The law does not spell out how the determination and verification must be done.
Police officers almost always get identification from people they arrest, but most police departments don't use that information to check everybody's immigration status, he said.
"This becomes a very large, unfunded mandate for police departments," Michalowski said.
2. During any stop, detention or arrest, a police officer must try to determine a person's immigration status if the officer has reason to suspect the person is here illegally. An exception exists if making that determination might obstruct an investigation.
• The law says: "For any lawful 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 of this state where reasonable suspicion exists that the person is an alien and is unlawfully present in the United States, a reasonable attempt shall be made, when practicable, to determine the immigration status of the person, except if the determination may hinder or obstruct an investigation."
• What it means: The language - which was changed Thursday night to clarify lawful contact - effectively makes checking immigration status a "secondary enforcement" akin to the state's seat-belt laws, said Paul Senseman, the governor's spokesman.
The law doesn't force officers to go out looking for illegal immigrants, only to call immigration officials to determine the status when the officer develops a reasonable suspicion, Kris Kobach, a University of Missouri at Kansas City law professor who helped draft the bill, said in an interview with National Public Radio.
Kobach was Attorney General John Ashcroft's chief adviser on immigration law and border security from 2001 to 2003. He did not return phone calls from the Arizona Daily Star for this story.
He wrote in an op-ed for The New York Times that the law will most likely come into play after a traffic stop.
"A police officer pulls a minivan over for speeding. A dozen passengers are crammed in. None has identification. The highway is a known alien-smuggling corridor. The driver is acting evasively. Those factors combine to create reasonable suspicion that the occupants are not in the country legally," he wrote.
It's unclear if the law requires this determination to be made by a federal agent in person or over the phone.
The change in wording from "lawful contact" to "lawful stop, detention or arrest" would appear to exempt victims and witnesses from the law, but the statute still dictates a significant change in traditional priorities of law enforcement agencies, said Gabriel "Jack" Chin, of the University of Arizona's James E. Rogers College of Law. Chin has been reading statutes for 25 years and an article he co-wrote was mentioned five times in a recent U.S. Supreme Court decision, Padilla v. Kentucky, regarding the rights of illegal immigrants.
It will force officers to inquire about the immigration status of everyone they stop, detain or arrest, if there is a reasonable suspicion they are illegal immigrants, rather than focusing on determining the immigration status of people who have committed serious crimes or investigating more serious crimes, as they do now, Chin said.
"Police have to have priorities," Chin said. "They can't enforce every law against everybody. They have to decide what is most important and focus on that. Traditionally, they have focused on the most serious crimes."
The language also leaves much to the discretion of individual officers, which means it could be implemented quite differently by agencies and within agencies, regents professor Michalowski said.
And he's not sure the clarification in wording will help with the damage that might have already been done in terms of losing trust in immigrant communities that now fear any contact with police could lead to deportation.
"Once widespread fear has been created as it has in Latino communities in Arizona, a few minor word changes will not get the genie back into the bottle," Michalowski said.
Many law enforcement leaders have expressed concern that the law will discourage illegal immigrants from reporting crime to police for fear of deportation. That could diminish public safety for all residents if, for instance, a murderer or rapist is on the loose.
A Tucson police officer filed a lawsuit Thursday challenging the bill on this basis, claiming the legislation would hinder investigations in Latino neighborhoods.
3. People who officers suspect are here illegally must show one of four approved identification cards to prove they are in the county legally.
• The law says: "A person is presumed to not be an alien who is unlawfully present in the United States if the person provides to the law enforcement officer or agency any of the following:
• A valid Arizona driver license.
• A valid Arizona non-operating identification license.
• A valid tribal enrollment card or other form of tribal identification.
• If the entity requires proof of legal presence in the United States before issuance, any valid United States federal, state or local government issued identification."
What that means: If you are worried you might raise the suspicion of an officer because of your ethnicity or accent, it's best to carry your Arizona driver license or other documents that show you are here lawfully, immigrant advocates say.
Although a citizen or legal resident cannot be convicted under the new law, carrying proper ID will help to avoid having to go to jail while your immigration status is confirmed, Chin said.
But Kobach downplayed the need for anybody to carry identification in The New York Times op-ed.
"Arizona's law does not require anyone, alien or otherwise, to carry a driver's license," he wrote. "Rather, it gives any alien with a license a free pass if his immigration status is in doubt. Because Arizona allows only lawful residents to obtain licenses, an officer must presume that someone who produces one is legally in the country."
4. In a change made Thursday night by the bill's sponsors, the law prohibits police from using race to establish reasonable suspicion that someone is here illegally. The original bill prohibited using "solely" race.
• The law says: "A law enforcement official or agency of this state or a county, city, town or other political subdivision of this state may not consider race, color or national origin in implementing the requirements of this subsection except to the extent permitted by the United States or Arizona Constitution."
• What that means: The bill's sponsor, Rep. Russell Pearce, R-Mesa, said the original provision was relevant because 90 percent of people in the country illegally are from Mexico and Latin America. But after the change, he said the provision is probably unnecessary, as the U.S. Constitution already precludes racial profiling. What the change does, Pearce said, is remove a target for foes, both those in court and those criticizing the measure in speeches and demonstrations.
In The New York Times op-ed, Kobach wrote, "The Arizona law actually reduces the likelihood of race-based harassment by compelling police officers to contact the federal government as soon as is practicable when they suspect a person is an illegal alien, as opposed to letting them make arrests on their own assessment."
But Chin and Michalowski said the word alteration doesn't change the fact that this is a racial-profiling law. Michalowski said the removal of "solely" was a "public-relations" maneuver that likely won't change anything.
"With or without that one word the law increases the number of instances in which officers inclined to racially profile can do so," Michalowski said.
5. The law makes it a state crime to transport, conceal, harbor or shield illegal immigrants. There is an exception for child-protective-services workers, first responders, ambulance attendants and emergency medical technicians.
• The law says: "It is unlawful for a person who is in violation of a criminal offense to:
"1. Transport or move or attempt to transport or move an alien in this state, in furtherance of the illegal presence of the alien in the United States, in a means of transportation if the person knows or recklessly disregards the fact that the alien has come to, has entered or remains in the United States in violation of law.
"2. Conceal, harbor or shield or attempt to conceal, harbor or shield an alien from detection in any place in this state, including any building or any means of transportation, if the person knows or recklessly disregards the fact that the alien has come to, has entered or remains in the United States in violation of law.
"3. Encourage or induce an alien to come to or reside in this state if the person knows or recklessly disregards the fact that such coming to, entering or residing in this state is or will be in violation of law."
• What that means: The passage is borrowed from federal law and only applies to people who know or recklessly disregard the fact that the person is an illegal immigrant, Kobach told The Arizona Republic.
But Michalowski said the law puts friends and family members of illegal immigrants in danger of violating the law when they are together. The law "makes citizens and legal residents criminals for providing aid to these family members and friends," he said.
"There is nothing in SB 1070 that says the law cannot be turned on them if they initiate contact with or are questioned by police in relationship to some other criminal matter," he said.
Those scenarios probably wouldn't put somebody at risk, Chin said, but he's not sure because of the inclusion of the exceptions.
6. The law makes it a state crime for illegal immigrants to work in Arizona.
• The law says: "It is unlawful for a person who is unlawfully present in the United States and who is an unauthorized alien to knowingly apply for work, solicit work in a public place or perform work as an employee or independent contractor in this state."
• What that means: This is the most clearly written part of the statute and what should be the headline of any story about the new law, Chin said.
This makes any illegal immigrant who is working or trying to get work - for example, by showing up at popular gathering spots for day laborers - at risk of being arrested by an Arizona law enforcement officer. This is a big change, because previously, a non-citizen did not commit a state crime by working or seeking work, Chin said.
7. The law also makes it a state crime for somebody to stop on the street and pick up somebody for work, although it may be hard to prove - and because of the way the law is written this may still be OK as long as the driver pulls off the road first.
• Passage: "It is unlawful for an occupant of a motor vehicle that is stopped on a street, roadway or highway to attempt to hire or hire and pick up passengers for work at a different location if the motor vehicle blocks or impedes the normal movement of traffic. … It is unlawful for a person to enter a motor vehicle that is stopped on a street, roadway or highway in order to be hired by an occupant of the motor vehicle and to be transported to work at a different location if the motor vehicle blocks or impedes the normal movement of traffic."
• What it means: This is an attempt to make it a state crime to hire day laborers, but the way it's written it may be hard to prove without getting a confession, Chin said. As written, it seems to only make it illegal to block traffic in the street, Chin said.
The confusion in this section is a theme throughout the law, Chin said.
"I have never read a statute that was attempting to regulate an area but left so many issues open and ambiguous," he said.
But Kobach dismisses the arguments against the law as misrepresentations and defends its usefulness.
"The Arizona law hardly creates a police state," he wrote in The New York Times op-ed. "It takes a measured, reasonable step to give Arizona police officers another tool when they come into contact with illegal aliens during their normal law enforcement duties."
Contact reporter Brady McCombs at firstname.lastname@example.org or 573-4213. Howard Fischer of Capitol Media Services contributed to this report.