(1) Proof of participation in the illegal drug market in an action brought under this chapter shall be shown by clear and convincing evidence. Except as otherwise provided in this chapter, other elements of the cause of action shall be shown by a preponderance of the evidence.
(2) A person against whom recovery is sought, who has a criminal conviction pursuant to state drug laws or the Comprehensive Drug Abuse Prevention and Control Act of 1970, Public Law 91-513, 84 Stat. 1236, codified at 21 U.S.C. § 801 et seq., is estopped from denying participation in the illegal drug market. Such a conviction is also prima facie evidence of the person's participation in the illegal drug market during the two (2) years preceding the date of an act giving rise to a conviction.
(3) The absence of a criminal drug conviction of a person against whom recovery is sought does not bar an action against that person.