¶1(dissenting).
¶2I cannot agree with the majority’s conclusion that Instruction No. 15 established a mandatory presumption. The final sentence of the instruction stated, “This shall be considered with other evidence in this case.” I believe this sentence properly informs the jury that they could reject the presumption of knowledge. Furthermore, except for the final sentence, the jury instruction was a verbatim quote of Iowa Code section 321.81. Thus, the majority’s decision in this case necessarily requires a conclusion that the statutory provision is unconstitutional. I am troubled by the fact that our decision would have this effect when the parties have not addressed and we have not considered the constitutionality of the provision. It is far too important a question to decide in such an indirect manner.