Facebook's published advertising policies, while permitting many kinds of political advertising, do state that it will reject any kind of ad that promotes "the sale or use of weapons, ammunition, or explosives. This includes ads for weapon modification accessories." Ads cannot show "weapons of any kind, including pepper spray, non-culinary knives/blades/spears, tasers, nun-chucks, batons, or weapons intended for self-defense."
The policy received renewed media attention when the social-media platform rejected an ad featuring Georgia Congressional candidate Marjorie Green holding a semi-automatic weapon.