WASHINGTON -- Close your eyes, reach into your wallet and try to distinguish between a $1 bill and a $5 bill. Impossible? It's also discriminatory, a federal appeals court says.

The American Council of the Blind sued for such changes, but the government has been fighting the case for about six years.

The U.S. acknowledges the current design hinders blind people, but it argues that they have adapted. Some rely on store clerks to help, some use credit cards and others fold certain corners to help distinguish between bills.

"I don't think we should have to rely on people to tell us what our money is," said Mitch Pomerantz, the Council of the Blind president.

Others say they manage but not always easily.

"When I pay for something and I get change back, I'm very slow and methodical. I'll ask, 'Is this the 10? Is this the five? Is this the one?' " said Kim Charlson, the library director at the Perkins School for the Blind, which is Helen Keller's alma mater.

Some use electronic currency readers. But they can be expensive, and they sometimes have problems with new $20 bills.

"It's slow," said Sam McClain, who manages a snack shop in a legislative office building near the Georgia Capitol. He has a currency reader but usually relies on the honesty of his customers. "Sometimes I have 10 or 15 people in here, and I can't use it."

The court ruled 2-1 that such adaptations were insufficient under the Rehabilitation Act. The government might as well argue that there's no need to make buildings accessible to wheelchairs because handicapped people can crawl on all fours or ask passers-by for help, the court said.

"Even the most searching tactile examination will reveal no difference between a $100 bill and a $1 bill. The secretary has identified no reason that requires paper currency to be uniform to the touch," Judge Judith W. Rogers wrote for the majority.

Courts don't decide how to design currency. That's up to the Treasury Department, and the ruling forces the department to address what the court called a discriminatory problem.

That could still take years. But since blindness becomes more common with age, people in their 30s and 40s should know that, when they get older, "they will be able to identify their $1 bills from their fives, tens and twenties," said Pomerantz, of the Council of the Blind.

Redesigned bills could also mean more job opportunities, since employers often hesitate to hire blind workers for jobs handling money, said Charlson, of the Perkins School for the Blind.

"When there are so few things in your life that you've got total control over, being able to even take care of your own money is such a big step, without requiring someone to tell you whether you've got enough money to go out and get a beer or have a hamburger," she said.

The government could ask for a rehearing by the full appeals court or challenge the decision to the Supreme Court.

Treasury Department spokeswoman Brookly McLaughlin said the department was reviewing the opinion. She noted that the Bureau of Engraving and Printing, which prints the nation's currency, recently hired a contractor to consider ways to help the blind. The results will be available early next year, she said.

While the government has been fighting to overturn the lower court ruling, it has been taking some steps toward modifying U.S. currency for the visually impaired. The most recent currency redesign of the $5 bill introduced in March features a giant "5" printed in purple on one side of the bill to help those with vision problems distinguish the bill.

Indeed, the Treasury has previously considered making different sizes of bills but ran into opposition from makers of vending and change machines. Government lawyers raised this issue in court, saying it could cost billions to redesign vending machines. But the court said such data are murky, especially since one proposed solution would be to leave $1 bills unchanged.

Given recent U.S. redesigns, the appeals court ruled the U.S. failed to explain why adding more changes would be an undue burden. More than 100 other countries vary the size of their bills, a federal judge said in 2006, and others include at least some features to help the blind. The European Central Bank, for instance, worked closely with the blind when designing euro notes that varied in size and contained other easily recognizable features.

The appeals court said the U.S. never explained why such solutions wouldn't work here.

Not all blind people agree that U.S. money should be changed. The National Federation of the Blind sided with the government and told the appeals court that no changes were needed.

Charlie Richardson, the legally blind manager of Charlie's Express Stop inside the Capitol in Albany, N.Y., said he doesn't oppose changing the money but disagrees with the ruling.

"To actually be discriminated against is to have something denied to you," Richardson said. "We're not denied the use of money."

• Associated Press writers Greg Bluestein in Atlanta and Valerie Bauman in Albany, N.Y., contributed to this report.