A federal appeals court heard oral arguments this week in a case that challenges the use of class actions in civil rights lawsuits alleging procedural due process violations.

The class action, which the American Civil Liberties Union of Southern California brought 11 years ago, alleges that immigrant detainees have been deprived of their constitutional right to a bond hearing. But much of the arguments on Monday before the U.S. Court of Appeals for the Ninth Circuit focused on whether the Federal Rule 23 of Civil Procedure, which governs class actions, could be applied when the alleged due process violations may be too varied as to each detainee in order to establish commonality.