Richard Wolf

USA TODAY

WASHINGTON — The Supreme Court struggled Wednesday to find a clear reason why pregnant women deserve accommodations at work.

Faced with Peggy Young's lawsuit against United Parcel Service for refusing to give her light duty during her pregnancy, conservative justices said she was seeking a form of "most favored nation" status used in trade agreements — treatment equal to the best-treated workers.

Liberal justices saw it differently, arguing that Young was "least favored" by UPS because very few workers with sicknesses, injuries or disabilities were denied the accommodations she sought.

"No one who wanted a dispensation didn't get it, except pregnant women," Justice Ruth Bader Ginsburg said.

The two sides left those justices in the middle wondering how to square sympathy for Young with the letter of the law — in this case, the Pregnancy Discrimination Act of 1978, which says pregnant workers should be treated equally to those who are "similar in their ability or inability to work."

All Young wanted in 2006 was what her doctor recommended — tasks that required lifting no more than 20 pounds, rather than the 70 pounds her part-time job as a UPS driver called for. But she was forced to take unpaid leave without benefits. And two lower federal courts ruled against her.

"This is not what we intended on from the beginning," Young said as women's rights groups protested her plight outside court. "We just wanted right to be done."

UPS said its policy was right. Her pregnancy, it said, did not meet any of its three criteria for a workplace accommodation — an on-the-job injury, a disability recognized by the Americans with Disabilities Act (ADA) or the loss of federal certification to drive.

Potential supporters on the court, such as Justices Stephen Breyer and Anthony Kennedy, had trouble seeing pregnancy discrimination in a policy that treated at least some other workers the same. The key, Breyer said, might come down to how many others were denied accommodations.

Young's most vocal support came from Justice Elena Kagan, who suggested a "middle ground" in which a pregnant worker would be given the benefit of the doubt, but her employer could defend giving preference to other workers for reasons such as seniority.

That might solve concerns raised by the U.S. Chamber of Commerce, which argued in a brief to the court that a literal reading of the 1978 law would give pregnant workers an advantage over nearly all others, including veterans and those with seniority, on issues that go beyond physical accommodations.

The case could turn out to be more important for other pregnant workers and employers than it is for Young or UPS. Young left the company in 2009 and is seeking back pay and benefits. UPS is changing its policy on Jan. 1 to provide pregnant workers who seek it the type of disability accommodation Young sought for herself.

But across the nation, more than six in 10 women who give birth were employed during their previous 12 months, making Young's case of critical importance to them.

Recent years have seen a trend in favor of pregnant workers. Congress amended the ADA in 2008 to include pregnancy-related lifting restrictions as a disability. At least nine states now require employers to accommodate pregnant women; similar laws are under review in a half-dozen other states.

Still, the high court will be watched closely to see how it handles another in a series of women's rights cases. In recent years, the court ruled that women can be denied health insurance coverage for contraceptives, struck down a Massachusetts law requiring buffer zones around abortion clinics, refused to certify a class-action discrimination claim by female workers at Walmart and denied Lily Ledbetter's pay-discrimination claim against Goodyear Tire & Rubber.

The delicate gender politics of the pregnancy discrimination case was evident by the choice of attorneys at the podium. Young was represented by a man, University of Michigan law professor Samuel Bagenstos. UPS chose Gibson Dunn partner Caitlin Halligan, President Obama's first, failed nominee for the U.S. Court of Appeals for the D.C. Circuit.

Halligan jousted frequently with Kagan and Ginsburg, the most vocal skeptics of the UPS policy. She said the company's policy was aimed at differentiating between what happens on and off the job.

"That's a far cry from a policy that singles out pregnant women," Halligan said.