Does Rule 704(b) permit a government expert witness to testify about certain roles in criminal activity, that people in those roles are knowing participants in the criminal activity, and then that a particular defendant played one of those roles in the case at bar?

ESTION PRESENTED Rule 704(b) of the Federal Rules of Evidence provides: In a criminal case, an expert witness must not state 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. Those matters are for the trier of fact alone. The question is: Does Rule 704(b) permit a government expert witness to testify about certain roles in criminal activity, that people in those roles are knowing participants in the criminal activity, and then that a particular defendant played one of those roles in the case at bar? i