Whether the Eighth Circuit misinterpreted the but-for causation test in light of the government's burden, and inappropriately applied the contributing causation test rejected by this Court in Burrage

QUESTIONS PRESENTED I. WHETHER THE EIGHTH CIRCUIT MISINTERPRETED THE BUT-FOR CAUSATION TEST IN LIGHT OF THE GOVERNMENT’S BURDEN, AND INAPPROPRIATELY APPLIED THE CONTRIBUTING CAUSATION TEST REJECTED BY THIS COURT IN BURRAGE? II. WHETHER IN DOING SO, THE EIGHTH CIRCUIT'S OPINION IS IN CONFLICT WITH THE SEVENTH CIRCUIT'S DECISION IN GAYLORD V. UNITED STATES? III. WHETHER THE EIGHTH CIRCUIT'S ALTERNATIVE HOLDING MISINTERPRETED BURRAGE AND APPLIED AN ERRONEOUS SPECIAL RULE OF INDEPENDENTLY SUFFICIENT CAUSE? ll