In Sandstrom, the Court confronted the presumption that the defendant “intended the natural and probable consequences of his act,” but avoided deciding the constitutionality of that presumption. Instead, deeming the jury instruction in that case to be consistent with the black letter of Allen, the Court concluded that the instruction nevertheless could have been misunderstood by the jury to impose on the defendant a burden to “disprove” the presumption. This would unconstitutionally put upon the defendant the burden of proving the lack of mens rea. The holding reemphasized the point of Allen that jury instructions must be very clear and should not tread close to the line of even suggesting to the jury that the defendant had the burden of disproving an element.
This approach of looking at jury instructions makes eminent sense: even if a statutory presumption is stated in absolute terms (proof of A means that the jury must find B), if the trial judge refuses to instruct in such terms, the jury’s deliberations are not affected because the jury will never hear or see the statute. Similarly, if the statutory presumption is exceedingly permissive (“if the jury finds A, it may, but need not under any circumstances, conclude B”), a judicial instruction that “if you find A, you must find B unless defendant convinces you beyond a reasonable doubt of non-B” would run afoul of Winship.
The thrust of these cases is that presumptions are on weak ground as we enter the twenty-first century, and that they are likely to be valid only if (1) the link between A and B is very strong and (2) the judge’s instructions so weaken the “mandatory” nature of the “presumption” and make it so fact-specific to the case at hand that it is no longer an abstract proposition.
The Code does not recognize mandatory presumptions, preferring that when the legislature wishes to require the defendant to carry the burden of production or persuasion, it say so explicitly. (As already noted, the Code itself establishes only a small handful of such claims.) On the other hand, §1.12(b) allows the court to instruct the jury that it may (not must) use a permissive inference on its way to finding the presumed fact.
Not everything a defendant says in an adversarial setting is a “defense”. If a defendant in a tort case denies an allegation of negligence by saying that the light was green when he went through it, he is not raising a “defense” but challenging the very heart of the plaintiff’s case. On the other hand, there are “true” (affirmative) defenses in civil law. For example, demonstrating that the case was not brought within the time allowed by the statute of limitations is an affirmative defense for which the defendant carries the burden.