Using the example of a recent major terrorism prosecution, this Article addresses “coventurer hearsay” in the context of the ongoing Confrontation Clause debate concerning the United States Supreme Court’s decision in Crawford v. Washington. Courts have recently begun admitting hearsay evidence pursuant to a revisionist interpretation of the coconspirator statement exception to the hearsay rule. Under the new “lawful joint venture” theory, a hearsay statement may be admitted as a coconspirator statement if made in furtherance of a “joint undertaking”—defined as pretty much any cooperative activity—even if the “conspiracy” is not illegal. Because this new interpretation of an old hearsay exception cannot plausibly be described as “firmly rooted” in American law, nor does the hearsay included in the new exception bear “indicia of reliability,” coventurer hearsay would have been inadmissible at criminal trials under pre-Crawford Sixth Amendment jurisprudence. The overwhelming majority of coventurer statements, however, are not “testimonial,” meaning that current Confrontation Clause law does not prohibit their use against criminal defendants. Accordingly, coventurer hearsay demonstrates that defendants suffer prejudice from the Court’s reinterpretation of the Sixth Amendment.