1. (10) Carries a firearm, whether loaded or unloaded, or any other weapon readily capable of lethal use into any school, onto any school bus, or onto the premises of any function or activity sponsored or sanctioned by school officials or the district school board.
2. Subdivisions (1), (8), and (10) of subsection 1 of this section shall not apply to the persons described in this subsection, regardless of whether such uses are reasonably associated with or are necessary to the fulfillment of such person's official duties except as otherwise provided in this subsection.....:
(1) All state, county and municipal peace officers who have completed the training required by the police officer standards and training commission pursuant to sections 590.030 to 590.050 and who possess the duty and power of arrest for violation of the general criminal laws of the state or for violation of ordinances of counties or municipalities of the state, whether such officers are on or off duty, and whether such officers are within or outside of the law enforcement agency's jurisdiction, or all qualified retired peace officers, as defined in subsection 11 of this section, and who carry the identification defined in subsection 12 of this section, or any person summoned by such officers to assist in making arrests or preserving the peace while actually engaged in assisting such officer
3. Subdivisions (1), (5), (8), and (10) of subsection 1 of this section do not apply ..... Subdivision (10) of subsection 1 of this section does not apply
if the firearm is otherwise lawfully possessed by a person while traversing school premises for the purposes of transporting a student to or from school, or possessed by an adult for the purposes of facilitation of a school-sanctioned firearm-related event or club event.