(a) Any person who, within this state, possesses any assault weapon, except as provided in this chapter, shall be punished by imprisonment in a county jail for a period not exceeding one year, or by imprisonment pursuant to subdivision (h) of Section 1170.
(b) Notwithstanding subdivision (a), a first violation of these provisions is punishable by a fine not exceeding five hundred dollars ($500) if the person was found in possession of no more than two firearms in compliance with Section 30945 and the person meets all of the following conditions:
(1) The person proves that he or she lawfully possessed the assault weapon prior to the date it was defined as an assault weapon.
(2) The person has not previously been convicted of a violation of this article.
(3) The person was found to be in possession of the assault weapon within one year following the end of the one-year registration period established pursuant to Section 30900.
(4) The person relinquished the firearm pursuant to Section 31100, in which case the assault weapon shall be destroyed pursuant to Sections 18000 and 18005.