The Supreme Court heard arguments Monday in a case challenging government surveillance under the Foreign Intelligence Surveillance Act. The American Civil Liberties Union brought the case on behalf of lawyers, journalists and human rights researchers who say the monitoring of overseas communications violates their constitutional rights. The U.S. government has fought for dismissal on the grounds that the plaintiffs cannot prove their communications have been monitored. But the ACLU argued Monday that such proof is impossible to obtain since spy targets are considered secret. In a statement, the ACLU’s Jameel Jaffer said he was encouraged by Monday’s arguments, saying: “The court seemed appropriately skeptical of the government’s attempts to shield this sweeping surveillance law from meaningful judicial review.”