Election litter is a term used by some national and subnational governments to describe the unlawful erection of political advertising

Political campaign

A political campaign is an organized effort which seeks to influence the decision making process within a specific group. In democracies, political campaigns often refer to electoral campaigns, wherein representatives are chosen or referendums are decided...

 on private residences or property owned by the local government. Often, election signs may only be displayed on private property with permission for a certain time within the election, and may not exceed a certain size. When placed on public property or public rights of way without permission, or if left on private property for too long, they are often in violation of littering laws, and/or laws intended to prevent flyposting

Flyposting

Flyposting is a guerilla marketing tactic through the act of placing advertising posters or flyers in legal or illegal places. In the United States, these posters are known as bandit signs, snipe signs, or street spam. Posters are adhered to construction site barricades, building facades, in...

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Election litter usually is defined as placing campaign signs on public, government-owned property, or on privately owned property (including residences) without the owner's permission.