On Thursday, the U.S. Supreme Court upheld an Arizona law that permits local officials to revoke the licenses of businesses that knowingly hire illegal workers. The decision makes sense in principle but not in practice.

Under the 2007 Legal Arizona Workers Act, business owners are required to use the federal E-Verify program to confirm if a person is authorized to work in this country. Employers must electronically check workers’ names against databases kept by the Social Security Administration and the Department of Homeland Security. Workers found to be ineligible have up to eight working days to straighten out the problem before employers would be required to fire them. If a company is found to have knowingly hired an undocumented worker once, it can have its licenses suspended; twice, the company may be shut down.

The problem with the Arizona statute is not that it penalizes employers who break the law. Businesses that hire undocumented immigrants should face fines or sanctions, as called for under current federal law (although many would disagree with the court’s conclusion that states may impose such penalties). The problem is that the law relies on E-Verify, which isn’t ready for prime time.

Until now, E-Verify has generally been used on a voluntary basis by employers because of concerns about its accuracy. Conservative estimates put the program’s error rate at just under 1 percent ― meaning that one out of every 100 legal job applicants could be found ineligible to work. Nearly half of those will not be able to fix the problem even though they are citizens or legal workers, according to the National Immigration Law Center. The reality is that the error rate may be much higher. Consider that in 2008, Intel Corp. reported that just over 12 percent of its workers were wrongly tagged as ineligible, according to the Migration Policy Center in Washington. Or that a survey by Los Angeles County of employees found an error rate of 2.7 in 2008 and 2.0 in 2009, according to a report submitted to the Board of Supervisors. The error rate is especially high in cities with large immigrant communities.

Furthermore, E-Verify doesn’t detect identity theft or prevent unscrupulous employers from moving their workforce off the books. Nor does the law guarantee employers that they will be immune from losing their licenses if E-Verify mistakenly allows them to hire an undocumented worker. That lack of protection may, as Justice Stephen G. Breyer noted in his dissent, persuade some business owners to avoid hiring those who look or sound foreign-born.

At the very least, the court’s ruling should prompt the Obama administration to act quickly to fix E-Verify and improve its accuracy. And the White House should seek a qualified candidate to serve as the Justice Department’s special counsel in charge of enforcing the anti-discrimination provisions of the immigration law.

But the court’s ruling doesn’t fix the bigger problem: the need for comprehensive immigration reform. Arizona and other states that have passed similar measures are stumbling to create their own immigration laws because the current system isn’t working. Thursday’s decision should put Washington on notice that in the absence of a federal solution, states will step in to fill the void.

(Los Angeles Times, May 27)