A wave of opposition to Arizona’s anti-immigrant law continues to swell from elected officials, civil rights groups, entertainers and attorneys who say the measure is discriminatory and unconstitutional and invites racial profiling.

On Thursday attorneys with the American Civil Liberties Union (ACLU), the Mexican American Legal Defense and Educational Fund (MALDEF) and the National Immigration Law Center (NILC) announced their partnership to challenge the controversial law in court.

“The Arizona community can be assured that a vigorous and sophisticated legal challenge will be mounted, in advance of SB 1070’s implementation, seeking to prevent this unconstitutional and discriminatory law from ever taking effect,” said Thomas A. Saenz, MALDEF president and general counsel, in a press statement.

Alessandra Soler Meetze, executive director of Arizona’s ACLU added, “This law will only make the rampant racial profiling of Latinos that is already going on in Arizona much worse.”

“If this law were implemented, citizens would effectively have to carry ‘their papers’ at all times to avoid arrest,” she noted. “It’s a low point in modern America when a state law requires police to demand documents from people on the streets.”

The law will deter immigrants from speaking to the police, said Linton Joaquin, general counsel for the NILC. “The inevitable result is not only to make immigrants more vulnerable to crime and exploitation, but also to make the entire community less safe, by aggressively discouraging witnesses and victims from reporting crimes,” he said.

The groups note the law also infringes on the constitutional supremacy of the federal government, by interfering with federal immigration power and authority.

Civil rights leader Dolores Huerta said, “What we are witnessing today is the blatant targeting of an entire American population, Latinos.”

Huerta added, “We must not give in one inch to Arizona’s effort to blame our community for all the ills of the state or their efforts to run us out. We have worked this land, built and maintained these buildings and sacrificed as much as any other. We must put an end to SB 1070.”

Multi-Grammy-winning artist and human rights advocate Linda Ronstadt said, “My family, of both German and Mexican heritage, has a long history in Arizona. It has been our diverse and shared history in this state that unites us and makes us stronger. What Gov. Brewer signed into law last week is a piece of legislation that threatens the very heart of this great state. We must come together and stop SB 1070 from pitting neighbor against neighbor to the detriment of us all.”

Colombian singer Shakira met with the police chief and mayor of Phoenix this week to raise concerns that the law violates human and civil rights. “It goes against all human dignity,” she said.

And at the Billboard Latin Music Awards Thursday evening in Puerto Rico, many Latin American artists denounced the law on live television, including pop star Ricky Martin, saying, “It makes no sense.”

In Chicago dozens of protestors demonstrated outside Wrigley Field Thursday as the Cubs began a four-game series against the Arizona Diamondbacks. Many said they support a national call to economically boycott the state.

Since the Arizona bill was signed, three lawsuits have been filed against it.

U.S. Attorney General Eric Holder has indicated the federal government, with President Obama’s support, may challenge the law.

At least three Arizona cities – Phoenix, Flagstaff and Tucson – are also considering legal action to block the law.

Although Obama called the measure “misguided” and irresponsible, he said the likelihood of passing immigration reform legislation this year is slim, because congressional lawmakers may lack the “appetite” to tackle immigration especially with upcoming midterm elections.

However immigrant rights leaders say reform cannot wait and efforts to push legislation through Congress are critical as thousands continue to be rounded up and separated from their familys every day.

Latino voters are closely watching where their elected representatives stand on the issue and expect them to act with courage, Latino leaders say. And they plan to utilize the power of their vote come November, they say.

According to federal data there were an estimated 10.8 million undocumented immigrants living in the U.S. on January 1, 2009. Others claim there are over 12 million.

Studies note most immigrants living in the U.S. are from Latin America, with some 6.7 million from Mexico and 1.33 million from Central American nations El Salvador, Guatemala and Honduras.

In 2009 the total population of Arizona totaled 6.6 million, including an estimated 460,000 undocumented immigrants.

Hundreds of vigils and mass protests are under way nationwide against the Arizona law and hundreds of thousands are expected to join demonstrations across the country on May 1.

Photo: Immigrant rights activists chanting “Boycott Arizona” protest outside Wrigley Field in Chicago as the Arizona Diamondbacks opened a four-game series against the Cubs, April 29. (AP/Nam Y. Huh)