Are statements made during a recorded phone call, standing alone, sufficient to sustain the Government's constitutional burden of proof in a drug case?

question presented for review is: Are statements made during a recorded phone call, standing alone, sufficient to sustain the Government’s constitutional burden of proof in a drug case? Question No. 2 Two federal agents offered extensive overview testimony about drug organizations and interpretations of drug lingo and recorded conversations pursuant to Rules of Evidence 701 & 702. The First Circuit, the D.C. Circuit, and the Fourth Circuit have authority circumscribing the ability of the Government to utilize such testimony; however, the Tenth Circuit appears to disagree with this authority. The question presented for review is: To what extent do Rules 701 and 702 limit the scope of opinion, overview, and interpretive testimony of federal agents in drug cases? i