With nearly $315 million in damages at stake, the U.S. Supreme Court appeared divided over whether 2000 USS Cole bombing victims and their families gave proper legal notice to Sudan eight years ago.

The justices heard hourlong arguments in Republic of Sudan v. Harrison, stemming from a default judgment won by the Cole plaintiffs who claimed Sudan provided material support to al-Qaida and Osama bin Laden. The terrorist attack in Yemen killed 17 sailors and injured 42 others.

During arguments, the justices struggled with an arcane issue that could force the Cole families — if they lose — to restart their difficult litigation filed in Washington in 2010 under the Foreign Sovereign Immunities Act, or FSIA. Did they comply with the act by mailing notice of their complaint to Sudan's U.S. Embassy? Or were they required by the act and international law to send it to the foreign minister's address in Sudan?