On Oct. 12, 2021, the U.S. Supreme Court will hear oral argument in Hemphill v. New York, in which the petitioner challenges an evidentiary ruling of the New York Court of Appeals. The case calls on the Supreme Court to examine the relationship between the Confrontation Clause and the open-the-door doctrine. More precisely, the question is this: Did Hemphill's lawyer open the door to the admission of testimonial hearsay otherwise barred by the Confrontation Clause by his actions in defending Hemphill at trial?