Robertson said US paper money violates the Rehabilitation Act, which prohibits discrimination on the basis of disability in government programs. The opinion was given after a four-year legal fight.
Electronic devices are available to help blind people differentiate between bills, but many contend that they are slow, expensive, and unreliable. Visually impaired shoppers frequently rely on store clerks to help them.
"It's just frankly unfair that blind people should have to rely on the good faith of people they have never met in knowing whether they've been given the correct change," said Jeffrey A. Lovitky, lawyer for the blind plaintiffs in the lawsuit.
Government lawyers argued that forcing the Treasury Department to change the size of the bills or add texture would make it more difficult to prevent counterfeiting.
Robertson was not swayed. "Of the more than 180 countries that issue paper currency, only the United States prints bills that are identical in size and color in all their denominations," he wrote.
Government lawyers said changing the way money feels would be expensive. Cost estimates ranged from $75 million in equipment upgrades and $9 million in annual expenses for punching holes in bills to $178 million in one-time charges and $50 million in annual expenses for printing bills of varying sizes.
