When the 'advice of counsel' is an industry expert on the CSA and the Analogue Act, and was the petitioner's compliance officer, how can that defense be excluded when trying to prove a lack of mens rea?

QUESTIONS PRESENTED 1. When the “advice of counsel” is an industry expert on the CSA and the Analogue Act, and was the petitioner’s compliance officer, how can that defense be excluded when trying to prove a lack of mens rea? 2. Did the Eighth Circuit err in holding that the District Court did not abuse its discretion under Federal Rules of Evidence 403, by excluding all evidence that petitioner retained attorney(s) and relied upon the advice of counsel in his dealings with alleged controlled substance analogues under the Controlled Substance Analogue Enforcement Act? 3. Does the phrase, “substantially similar” within the Controlled Substance Analogue Act allow unfair application and vagueness, by not affording citizens fair notice, while . allowing indiscriminate application and prosecution?