(1) A person is guilty of arson in the second degree when he starts a fire or causes an explosion with intent to destroy or damage a building:
(a) Of another; or (b) Of his own or of another, to collect or facilitate the collection of insurance proceeds for such loss.
(2) In any prosecution under this section, it is a defense that:
(a) No person other than the defendant had a possessory or proprietary interest in the building, 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 building for a lawful purpose.
(3) Arson in the second degree is a Class B felony.