Justice Sonia Sotomayor could soon decide if the U.S. Justice Department can move forward with a prosecution against Turkey's state-owned Halkbank, a looming under-the-radar ruling that could have serious ramifications for U.S.-Turkey relations – and one that could potentially serve as a catalyst for Turkish President Recep Tayyip Erdogan to hammer the U.S. and its interests.

Sotomayor is set to examine the case in the wake of the Second Circuit Court of Appeals' decision last year that the Justice Department could prosecute Halkbank. She has jurisdiction over cases originating from this appeals court.