Moments after signing Arizona's tough new immigration law in April, Gov. Jan Brewer was asked what an illegal immigrant looks like.

The question, posed during a news conference that was broadcast live on TV, seemed to catch Brewer off guard. After a long pause, she said, "I don't know what an illegal immigrant looks like. I can tell you that there are people in Arizona that assume they know what an illegal immigrant looks like. I don't know if they know that for a fact or not."

What does an illegal immigrant look like?

Her answer cut to the very heart of the controversy surrounding the law, which takes effect July 29. Although there are many people who assume they know what an illegal immigrant looks like, the fact is, it is impossible to tell a person's immigration status by appearance, experts say.

So despite assurances to the contrary, some civil-rights groups and others fear that enforcement of the law will lead to racial profiling. Several lawsuits already raise worries of civil-rights violations, and a group of Arizona law professors concluded the law authorizes enforcement based on ethnicity. That, they allege, would mean officers would end up harassing and possibly detaining people who aren't illegal immigrants.

The vast majority of illegal immigrants are Hispanic. But most Hispanics in Arizona are not illegal immigrants - they are legal residents or U.S. citizens, many with roots dating back generations.

The law has sparked fears that it will lead to racial profiling, the objectionable and often illegal police practice of using race or ethnicity as the main reason for deciding whether to stop someone to determine if he or she has committed a crime. Law-enforcement agencies are generally barred from using racial profiling in investigations in order to protect people from unlawful search and seizure and other civil-rights violations, though the practice is murkier when it comes to immigration enforcement. In recent years, several law-enforcement agencies across the country, including the Arizona Department of Public Safety, have agreed to take steps to guard against racial profiling after they have faced racial-profiling lawsuits.

Brewer and supporters of Arizona's Senate Bill 1070 say there is nothing in it that requires police to investigate people's immigration status because they are Hispanic. But while the law does not directly mention Latinos or Latino immigrants, Brewer and sponsors such as state Sen. Russell Pearce and state Rep. John Kavanagh have repeatedly linked the law to the federal government's failure to prevent illegal immigration along the border with Mexico.

Several lawsuits filed in federal court by civil-rights and other organizations contend the law is so vaguely written that it will lead to widespread racial profiling and other civil-rights violations of minorities by police who assume illegal immigrants look Hispanic and therefore will be more likely to question people about their immigration status based on their appearance or accent.

The U.S. Department of Homeland Security estimates there were 460,000 illegal immigrants in Arizona as of January 2009. Although there is no official breakdown, the majority are believed to be from Latin America.

The Pew Hispanic Center, a nonpartisan research organization in Washington, D.C., estimates that 7 million, or 59 percent, of the nation's 11.9 million undocumented immigrants are from Mexico, and 76 percent are Latinos, meaning they come from Mexico or some other Latin American country.

But there are also sizable numbers of illegal immigrants from non-Latin American countries. Pew estimates there are 1.3 million illegal immigrants from Asia and 525,000 from Europe and Canada living in the U.S.

During a recent stop in Phoenix, Ciaran Staunton, president of the Irish Lobby for Immigration Reform, said many Americans don't realize there are 50,000 illegal immigrants from Ireland living in the United States, including about 1,000 in the Phoenix area.

Many work in the same industries as illegal immigrants from Mexico, in construction or in restaurants, he said.

During a June 25 panel discussion about the new law hosted by the Arizona Latino Media Association, Kavanagh acknowledged that there are illegal immigrants from Canada but said many are buying up foreclosed homes, according to Nancy-Jo Merritt, a Phoenix immigration lawyer who was one of the other panelists.

Merritt said the comment suggested Kavanagh is unconcerned about illegal immigrants from Canada.

In a later interview with The Republic, Kavanagh said the comment was a joke.

"I believe there is a threat from both borders and all illegal immigrants should be apprehended and deported," he said.

Public perception

Luis Plascencia, an anthropology professor at Arizona State University, says that over the years the public has come to associate illegal immigrants with Hispanics because of all of the attention paid to the border with Mexico. He says a very clear picture has emerged in the public's mind of what an illegal immigrant looks like: Dark-skinned Mexicans in work clothes driving pickups and who speak only Spanish or speak English with an accent. As a result, those are the people who are most likely to come under scrutiny by police under the law, Plascencia said.

The problem, Plascencia said, is that while many undocumented immigrants fit that description, so do many Latinos who are U.S. citizens or are in the country legally.

What's more, he said, many people who are illegal immigrants don't fit that profile and therefore are less likely to be questioned about their immigration status or citizenship.

A "light-skinned person" in a "three-piece suit carrying a briefcase" is not going to be suspected of being an illegal immigrant, Plascencia said.

"If your real concern is with the undocumented population, then you should go after the undocumented population - all of it. But if you are only targeting the undocumented who are Mexicans, then you are racially profiling," he said.

The law makes it a state crime to be in the country illegally. It states that an officer engaged in a lawful stop, detention or arrest shall, when practicable, ask about a person's legal status when reasonable suspicion exists that the person is in the U.S. illegally.

Assumptions

The congregation of a church in west Phoenix is made up mostly of Latinos. The Arizona Republic recently interviewed more than a dozen members willing to be asked about their citizenship. Several of those interviewed spoke limited English but were legal residents or naturalized U.S. citizens. Several others spoke English fluently and had lived in the United States most of their lives but were illegal immigrants.

Brian Morales, 17, who is a member of the congregation, has dark skin, a moustache and a light beard on his chin. The Deer Valley High School student was born in Phoenix, making him a U.S. citizen. But he is worried that police may not believe he is American because of his appearance.

"It's because I look Hispanic," said Morales, whose father is from Guatemala and whose mother is from Mexico. "They assume I am from Mexico because I have a moustache and a beard."

Morales, who doesn't have a driver's license, is planning to get an Arizona identification card in case he is stopped by police. Officials have said identification cards noting proof of legal immigration status or citizenship issued by government agencies in the United States are supposed to end an officer's suspicions about immigration status.

Kris Kobach, a University of Missouri-Kansas City law professor who helped write the law, says Latinos like Morales needn't be worried.

The law expressly prohibits police from using race, ethnicity or national origin as reasonable suspicion to question people about their immigration status.

"The law goes to extraordinary lengths to prohibit racial profiling," Kobach said. "It's perfectly legal to be of Hispanic ethnicity and not have any English skills and to be driving a pickup with landscaping tools in the back. There is nothing illegal about that, and there would be no basis for an officer pulling them over. And if an officer did pull someone over just because a person was Hispanic and was driving a landscaping vehicle, that would be a violation of SB 1070."

Kobach went on to say that even if police stop someone for a legitimate reason, appearance cannot be used as a factor in deciding whether there is reasonable suspicion the person is in the country illegally, even in combination with other factor's such as the inability to speak English or presenting a foreign driver's license or passport.

'False positives'

A training video created by the state's police licensing board instructs officers not to use race or ethnicity to enforce the law. Officers, however, can consider language in conjunction with other factors in deciding whether reasonable suspicion exists, including foreign-vehicle registration, demeanor and whether the stop has occurred in an area where "unlawfully present aliens are known to congregate looking for work," according to the video by the Arizona Peace Officer Standards and Training Board.

But Carissa Hessick, a criminal-law professor at Arizona State University, said she believes Arizona's law will lead to racial profiling. She is one of four law professors from ASU and the University of Arizona who wrote a report analyzing the state's new immigration law.

The professors concluded that the law "authorizes racial profiling." On one hand, the law states that law-enforcement officers "may not consider race, color or national origin." But it also makes an exception to the extent those factors are permitted by the United States or Arizona Constitution, she said. Federal and Arizona courts have ruled that ethnicity, when considered as one of many factors, can be used to enforce immigration laws, she said.

"Unfortunately, the constitutional standard we have is not a very high threshold for police to have," Hessick said. "And you are going to have an awful lot of false positives."

As a result, Hessick predicts, police will "sweep up an awful lot of people here who are legal residents, who are American citizens, and that is going to be a burden that is going to be disproportionately felt by a particular group here in Phoenix, and that is unfair."

Reach the reporter at daniel.gonzalez@arizonarepublic.com or 602-444-8312.