Boulder, CO Public Conduct: Loud Party Ordinance (2026)

Section 5-3-11, "Nuisance Party Prohibited," makes it a violation for any owner, occupant, tenant, or other person with possessory control of a premises, individually or jointly, to sponsor, conduct, host, or permit a social gathering that becomes a public nuisance, so long as the nuisance was either intended or reasonably anticipated under a reasonable-person standard. A gathering becomes a nuisance under Subsection (b) when attendees' conduct at the gathering site or on neighboring public or private property triggers violations including third-degree assault, brawling, threatening bodily injury, obstructing public streets or buildings, fighting words, damaging property, trespass, fires on public property, littering, graffiti, obstructing a peace officer, false reports, fireworks, public urination, underage alcohol possession or sales, excessive decibel levels, disrupting a neighbor's quiet enjoyment, unreasonable noise, unlawful trash disposal, obstructing traffic, or open burning.

Subsection (c) adds a stand-alone trigger specific to house parties: an open keg of beer located in a yard adjacent to a street, on a front porch visible to the public, or in a side yard visible from the street, sidewalk, or a neighboring property is itself deemed a public nuisance. Once a police officer declares the gathering a nuisance, Subsection (d) requires every participant to stop and disperse immediately, and anyone not living at the address must leave the premises at once; failing or refusing to obey that dispersal order is itself a violation. The ordinance traces to Ordinance No. 7126 (2001) and was last amended by Ordinance No. 8531 (2022).