Civil rights groups on May 29 sued Arizona to block a 2011 law banning abortions based on the race or sex of the child that makes it a felony to knowingly provide a sex- or race-based abortion.

Lawyers for the American Civil Liberties Union of Arizona said the law unconstitutionally singles out Asian and black women based on stereotypes and the sponsors’ beliefs that Asian and black women may choose an abortion because of race or the baby’s sex. Arizona is the only state that bans race-based abortions, although others bar abortions because of sex.

The ACLU filed the lawsuit on behalf of two civil rights groups and wants an injunction blocking the law, which makes it a felony for anyone to knowingly perform or provide financing for an abortion sought based on race or gender. The law also requires doctors to question patients and file an affidavit swearing that’s not the reason for the abortion.

Republican Rep. Steve Montenegro, a co-sponsor of the 2011 law, said it’s designed to prevent discrimination.

“We don’t want to discriminate based on somebody’s sex or somebody’s race,” said Montenegro of Litchfield Park. “This has to do with protecting the dignity of life and not allowing abortions to be performed based on the sex of the baby or the race of the baby. That’s what this is about.”

The groups suing, the National Association for the Advancement of Colored People’s Maricopa County branch and the National Asian Pacific American Women’s Forum, disagree.

“This law is clearly a wolf in sheep’s clothing that purports to be about achieving equality for women when in reality it’s an attempt to control our reproductive decisions-making,” said Miriam Yeung, NAPAWF’s executive director. “We hope the judgment in this case will expose the true intentions of the politicians behind these abortion bans and show unequivocally that they discriminate against women of color, Asian-American and African-American in particular.”

The case alleges the law violates the 14th Amendment’s equal protection clause. “The long history of jurisprudence … says laws passed with a discriminatory intent and racial stereotypes cannot stand, period. Cannot stand,” said Dan Pochoda, an ACLU lawyer. “And it is clear from the legislative history that that was the basis for the decision-making by the Legislature and the governor in this case.”

Some Asian cultures value male children, and lawmakers were concerned that female babies would be aborted as more Asians immigrated to the state, according to legislative history cited in the lawsuit. The high rate of abortions in the African-American community was cited as proof blacks were using abortion to “de-select” their own race, the suit said.

The lawsuit comes just months after a federal judge blocked a 2012 Arizona law that banned any public funds from going to Planned Parenthood of Arizona for non-abortion women’s health care because the group also provides abortion services. The U.S. Supreme Court refused to overturn a similar decision on an Indiana law on Tuesday, but the Arizona attorney general is continuing an appeal on the ruling to the 9th U.S. Circuit Court of Appeals.

The 2011 Arizona law banning race- and sex-based abortions is the only state law in the nation that bans race-based abortions, according to the New York-based Guttmacher Institute, which tracks U.S. abortion laws. Three other states, Illinois, Pennsylvania and Oklahoma, ban sex-based abortions, although the Illinois law isn’t enforced because of a court settlement, according to Elizabeth Nash, the group’s state issues manager.

North Dakota and Kansas enacted sex-based abortion bans this year, but they’re not yet in force. The North Dakota law also bans abortions because the fetus has a birth defect.

A Republican Arizona congressman, Trent Franks, has introduced a federal law similar to Arizona’s in recent years, but it has failed to win passage.