(1) Unless exempt under subsection (3) of this section, it is unlawful for any person to knowingly open carry a firearm or other weapon, as defined in RCW 9.41.300(1)(b), while knowingly being in the following locations:

(a) The west state capitol campus grounds; any buildings on the state capitol grounds; any state legislative office; or any location of a public state legislative hearing or meeting during the hearing or meeting; or

(b) City, town, county, or other municipality buildings used in connection with meetings of the governing body of the city, town, county, or other municipality, or any location of a public meeting or hearing of the governing body of a city, town, county, or other municipality during the hearing or meeting.

(a) "Buildings on the state capitol grounds" means the following buildings located on the state capitol grounds, commonly known as Legislative, Temple of Justice, John L. O'Brien, John A. Cherberg, Irving R. Newhouse, Joel M. Pritchard, Helen Sommers, Insurance, Governor's Mansion, Visitor Information Center, Carlyon House, Ayer House, General Administration, 1500 Jefferson, James M. Dolliver, Old Capitol, Capitol Court, State Archives, Natural Resources, Office Building #2, Highway-License, Transportation, Employment Security, Child Care Center, Union Avenue, Washington Street, Professional Arts, State Farm, and Powerhouse Buildings.

(c) "West state capitol campus grounds" means areas of the campus south of Powerhouse Rd. SW, south of Union Avenue SW as extended westward to Powerhouse Rd. SW, west of Capitol Way, north of 15th Avenue SW between Capitol Way S. and Water Street SW, west of Water Street between 15th Avenue SW and 16th Avenue SW, north of 16th Avenue SW between Water Street SW and the east banks of Capitol Lake, and east of the banks of Capitol Lake.

(3) Duly authorized federal, state, or local law enforcement officers or personnel are exempt from this section when carrying a firearm or other weapon in conformance with their employing agency's policy. Members of the armed forces of the United States or the state of Washington are exempt from this section when carrying a firearm or other weapon in the discharge of official duty or traveling to or from official duty. Fully uniformed color guard and honor guard affiliated with a veterans' service organization recognized by the Washington department of veterans affairs, or affiliated with the national sons of the American revolution or sons of union veterans of the civil war, are exempt from this section when carrying a firearm or other weapon while actively participating in, walking to, operating a vehicle during, and when leaving permitted events. The department of enterprise services may make such reasonable rules, regulations, and orders as may be necessary for the proper administration and enforcement of this subsection.

(6) A city, town, county, or other municipality must post signs providing notice of the restrictions on possession of firearms and other weapons under this section at any locations specified in subsection (1)(b) of this section.