PHOENIX - Defending its legality, Gov. Jan Brewer on Friday signed the toughest state law in the country designed to combat illegal immigration.

The governor rejected claims that the legislation, which gives police more power to stop and detain those not in this country legally, amounts to legalized racial profiling. She said the measure contains sufficient protections to individual constitutional rights.

And if that isn't enough, Brewer signed an executive order requiring that all police officers get proper training about when they can - and cannot - stop and question people about their immigration status.

The governor pointed out, both in her statement and that executive order, that the new law prohibits police from using race or ethnicity as the sole factor in determining whether to pursue an inquiry.

But she conceded that it does permit either to be used as one factor for an officer's consideration. And she defended the language.

"We have to trust our law enforcement," Brewer said.

"Police officers are going to be respectful," the governor continued. "They know what their jobs are, they've taken an oath. And racial profiling is illegal."

But Phoenix attorney David Selden, who was involved in unsuccessfully challenging a 2006 state law aimed at companies that knowingly hire illegal immigrants, said allowing race to be used as a factor at all is unconstitutional.

"That was a strategy used by white segregationists when they were trying to gut the (federal) civil-rights bill," he said. Selden suggested the same logic may be at work here.

"If they're not going to allow racial profiling, let's get 'race' out of it entirely," he said, rather than continuing to let police consider it.

Sen. Russell Pearce, R-Mesa, who crafted the legislation, defended the language. He said it recognizes that 90 percent of those who come to this country illegally are from Mexico or points south.

"You can't just say it's not ever a factor," he said. "It may be."

He said only certain people should be concerned about the law. "If you're here illegally, you should be concerned, just like if you drive drunk," he said. "The law is going to be enforced."

The governor's signature marks "one of the darkest days in Arizona's history," said Rep. Kyrsten Sinema, D-Phoenix. At the same time, Sinema sought to calm fears in the Hispanic community, saying she is confident a court will step in and declare the law unconstitutional, preventing it from taking effect as scheduled in early August.

Several groups, including the Mexican American Legal Defense and Education Fund, already have vowed to sue.

Brewer said she expects the new law to survive "in most areas," but did not elaborate.

She also said those who believe the law will lead to civil-rights violations are "alarmists," saying there has been "a lot of misinformation" in the media about what's in the bill.

"But there are people who are alarmists, who want to cause chaos, and they particularly don't want to always listen to the facts," the governor said.

Attorney General Terry Goddard said those who challenge the law may have a case.

Goddard said he won't be involved in deciding how and whether to defend the statute, as he is running against Brewer for governor and publicly called on her to veto the measure. Those determinations, he said, will be made independently by his chief deputy.

But Goddard said that, as a lawyer, there are elements of the law that could be troubling - depending on how the statute is enforced.

One is that ability to use race or ethnicity as a factor in determining whether there is "reasonable suspicion" to question someone stopped for some other legitimate reason about their immigration status.

Brewer brushed aside concerns that illegal immigrants who are crime victims or witnesses won't come forward, for fear of being questioned about their immigration status. That is based on language saying that when police officers make an official contact with anyone, a "reasonable attempt shall be made, when practicable, to determine the immigration status of the person."

Brewer, however, noted there is an exception if making that inquiry "may hinder or obstruct an investigation."

But Goddard pointed out that is based on each officer's individual determination.

Another section of the measure prohibits governments from limiting the ability of their officers to enforce federal immigration law. And any citizen who believes a community is violating that can file suit.

There was a lot of political pressure on Brewer to sign the controversial measure.

All three of her Republican foes in the gubernatorial primary are on record urging a signature. And every Republican legislator, except Sen. Carolyn Allen of Scottsdale, voted for the legislation.

Passage of the bill came just weeks after Cochise County rancher Robert Krentz was shot to death. It is presumed the killer was an illegal border crosser.

Brewer, however, sidestepped the question of how politics figured into her decision.

"I would like to believe that any politician, when they are elected, after they're elected, they do what's right for the people of Arizona," she said. And then, speaking of herself in the third person, she said, "I think it's very, very important that the people out there understand that Governor Jan Brewer of the great state of Arizona, would always do what's right for the people of Arizona."

The governor scheduled her news conference at an auditorium in a state-owned building about a mile from the Capitol.

The location not only provided space for the local and national media interested in the issue but also created some separation from the approximately 2,000 people who gathered in the mall between the House and Senate.

Most of them appeared to be high school or college students.

A rally in downtown Tucson was much smaller, ranging in size from 400 to 800 at various times during the day. The crowd consisted mostly of young people, and protesters wandered between the state building on West Congress Street and Armory Park.

"It's already signed into law, but we can definitely show our discontent," said Raul Rodriguez, a Pima Community College student. "It's just not right. I think it opens the door for racial profiling."

Tucsonan Jessica Pacheco cited two reasons for her strong opposition to the new law. "We cannot afford to pay for the measures it calls for," Pacheco said. "And, inevitably, the rights of U.S. citizens will be compromised by the passage of this bill."

Said Tucsonan Peter Sundt: "It's a total outrage. It's the beginning of a police state."


Star reporters Doug Kreutz and Phil Villarreal contributed to this story.