After reviewing the charge as a whole, we conclude that the giving of Instruction No. 4 was prejudicial error for the reasons stated hereinafter. While the giving of an instruction on contributory fault was warranted by the evidence, the instruction did not correctly set forth all the essential elements of contributory fault under the applicable substantive law of Missouri. It was therefore improperly included in the charge.
Under Missouri law an obvious or apparent danger is “pertinent” to the issue of whether McGowne was “contributorially” at fault, Higgins v. Paul Hardeman, Inc., supra, 457 S.W.2d at 947 (Mo.App.1970), but does not alone constitute a defense to a submissible case of strict liability under Section 402 A, supra, for the following reasons.
Under the substantive law of Missouri contributory fault is an affirmative defense in a strict liability action under Section 402 A, supra. Means v. Sears, Roebuck and Co., 550 S.W.2d 780, at 787 note 6 (Mo. en banc 1977); Missouri Approved Jury Instructions, 3rd Ed. 1981 (MAI) Chapter 32.00 on “Affirmative Defenses”, Instruction No. 32.23. And the burden of proof is on the party asserting an affirmative defense to establish all the elements of that defense. See cases cited in MAI, under Instruction No. 3.01. Because Instruction No. 4 did not require proof of all the elements of contributory fault, which were and are set forth in Instruction No. 32.23 of MAI cited above, the instruction incorrectly stated the law of Missouri on the affirmative defense of contributory fault.
Appellee Challenge-Cook contends that Instruction No. 4 is a correct statement of Missouri law because it was presented as a converse instruction to the appellants’ verdict directing instruction, and not as an instruction on contributory fault. In this connection, appellee argues that, in a strict liability action based on the failure to warn, liability does not exist if the defect is open or obvious because there is no duty to warn of an open and obvious danger. Appellee argues that this conclusion is derived from Restatement (Second) of Torts, § 402 A Comment i, which states that in order for a product to be unreasonably dangerous “[t]he article sold must be dangerous to an extent beyond that which would be contemplated by the ordinary consumer who purchases it, with the ordinary knowledge common to the community as to its characteristics.”
We conclude that the instruction is not a correct converse instruction for reason that it does not properly submit the absence of an essential element of strict liability under Section 402 A of the Restatement, supra, and under the law of Missouri.
Further, viewing Instruction No. 4 as an “affirmative converse” instruction, submitting independently a full defense, will not justify its inclusion in the charge. In this view the instruction is an erroneous verdict directing instruction. For example, in a strict liability action, an analogous erroneous affirmative converse instruction was condemned in Shephard v. Ford Motor Co., 457 S.W.2d 255, at 258 (Mo.App.1970). Affirmative converse instructions and the frequent error in their use are discussed in Thomas, Converse Instructions Under MAI, 42 Mo.L.Rev. 175, Part VI at pages 200-206.
The obviousness of a defect or danger is material to the issue whether a product is “unreasonably dangerous”. Cf. Annotation, Products Liability: Product as Unreasonably Dangerous or Unsafe Under Doctrine of Strict Liability in Tort, 54 A.L.R.3d 352, at 367-368 and cases therein cited. We conclude, however, that Instruction No. 4 was not a legally correct converse of the “unreasonably dangerous” element. The issue is not whether a jury can conclude that danger is obvious or apparent, but is whether the jury can conclude that the danger is obvious and apparent to the extent that the product was not “unreasonably dangerous”. Because Instruction No. 4 did not correctly set forth the effect of an obvious danger upon the “unreasonably dangerous” element, we conclude that the instruction was an incorrect statement of the substantive law of Missouri on that issue.