The issue may be moot for states if Congress takes action.
Republican Sen. John Sununu of New Hampshire, along with Democratic Sen. Daniel Akaka of Hawaii, filed a bill last year to repeal the law. Sununu expects similar legislation will be introduced soon.
"The federal government should not be in charge of defining and issuing drivers' licenses," Sununu said in a statement.
You'd think they would have thought of that when they voted for it.