A civil gang injunction or CGI is a type of restraining order issued by courts in the United States prohibiting gang members in particular cities from participating in certain specified activities. It is based on the legal theory that gang activity constitutes a public nuisance that can prevent non–gang members of the community from enjoying peace and public order. An injunction is obtained against the gang itself, after which the police and district attorney may decide against whom they will enforce it upon. Law enforcement use gang injunctions as a tool to label people as gang members and restrict their activities in a defined area (ACLU).