Pamela Karlan, representing the challengers, said they’ve alleged they voted absentee in the past and would like to do so again in the future. “Our allegation is about a discrimination claim,” and there is a concrete injury because others are given the option that the younger voters do not have, she added.

Karlan, a professor at Stanford Law School, said Wednesday “it is clear that young voters are worse off than older voters,” and that is an abridgment under the Twenty-Sixth Amendment. Like the Fifteenth and Nineteenth amendments—which prohibit governments from denying a citizen the right to vote based on race or gender—the Twenty-Sixth Amendment bars restrictions based on age, she added.

“The problem is the text of the Constitution doesn’t allow them to do that,” Karlan asserted. And the Twenty-Sixth Amendment’s “deny or abridge” language is a bar on discrimination, because the US Supreme Court has “repeatedly said”—in cases involving the Fifteenth and Nineteenth amendments—that discrimination is what that phrase forbids.