On Monday, a Turkish-Iranian gold trader testified at the trial of a Turkish bank executive that he had paid bribes in order to secure his release from a Turkish jail in 2013. The trader, Reza Zarrab, plead guilty to charges that he took part in a scheme to help Iran avoid US sanctions, and is testifying against Mehmet Hakan Atilla, an executive at Turkey’s state-owned Halkbank on trial for similar charges.