Mohamud is appealing his 2013 conviction on grounds that he was entrapped by undercover federal agents posing as al-Qaida members and the warrantless surveillance of his foreign communications violated his constitutional rights. It marks the first time a federal appeals court is considering whether the National Security Agency’s foreign surveillance programs — the same ones that came under scrutiny after the Edward Snowden leaks a few years ago — violate the Fourth Amendment rights of criminal defendants. Stephen Sady, Mohamud’s public defender, and another attorney with the American Civil Liberties Union urged the court for a new trial on grounds...