In any prosecution for the crime of reckless burning in the first or second degrees, it shall be a defense if the defendant establishes by a preponderance of the evidence that:
(a) No person other than the defendant had a possessory, or pecuniary interest in the damaged or endangered property, or if other persons had such an interest, all of them consented to the defendant's conduct; and
(b) The defendant's sole intent was to destroy or damage the property for a lawful purpose.
[ 1975 1st ex.s. c 260 s 9A.48.060.]