Today, the Supreme Court of the United States granted certiorari in one case:
Diaz v. United States, No. 23-14: This criminal drug-trafficking case involves interpretation of Rule 704(b) of the Federal Rules of Evidence, which bars expert witnesses from stating “an opinion about whether the defendant did or did not have a mental state or condition that constitutes an element of the crime charged or of a defense.” The question presented is: In a prosecution for drug trafficking—where an element of the offense is that the defendant knew she was carrying illegal drugs—does Rule 704(b) permit a governmental expert witness to testify that most couriers know they are carrying drugs and that drug-trafficking organizations do not entrust large quantities of drugs to unknowing transporters?