740 ILCS 147/10
"Course or pattern of criminal activity" means 2 or more gang-related criminal offenses committed in whole or in part within this State when:
"Course or pattern of criminal activity" also means one or more acts of criminal defacement of property under Section 21-1.3 of the Criminal Code of 1961 or the Criminal Code of 2012, if the defacement includes a sign or other symbol intended to identify the streetgang.
"Designee of State's Attorney" or "designee" means any attorney for a public authority who has received written permission from the State's Attorney to file or join in a civil action authorized by this Act.
"Public authority" means any unit of local government or school district created or established under the Constitution or laws of this State.
"State's Attorney" means the State's Attorney of any county where an offense constituting a part of a course or pattern of gang-related criminal activity has occurred or has been committed.
"Streetgang" or "gang" or "organized gang" or "criminal street gang" means any combination, confederation, alliance, network, conspiracy, understanding, or other similar conjoining, in law or in fact, of 3 or more persons with an established hierarchy that, through its membership or through the agency of any member engages in a course or pattern of criminal activity.
For purposes of this Act, it shall not be necessary to show that a particular conspiracy, combination, or conjoining of persons possesses, acknowledges, or is known by any common name, insignia, flag, means of recognition, secret signal or code, creed, belief, structure, leadership or command structure, method of operation or criminal enterprise, concentration or specialty, membership, age, or other qualifications, initiation rites, geographical or territorial situs or boundary or location, or other unifying mark, manner, protocol or method of expressing or indicating membership when the conspiracy's existence, in law or in fact, can be demonstrated by a preponderance of other competent evidence. However, any evidence reasonably tending to show or demonstrate, in law or in fact, the existence of or membership in any conspiracy, confederation, or other association described herein, or probative of the existence of or membership in any such association, shall be admissible in any action or proceeding brought under this Act.
"Streetgang member" or "gang member" means any person who actually and in fact belongs to a gang, and any person who knowingly acts in the capacity of an agent for or accessory to, or is legally accountable for, or voluntarily associates himself with a course or pattern of gang-related criminal activity, whether in a preparatory, executory, or cover-up phase of any activity, or who knowingly performs, aids, or abets any such activity.
"Streetgang related" or "gang-related" means any criminal activity, enterprise, pursuit, or undertaking directed by, ordered by, authorized by, consented to, agreed to, requested by, acquiesced in, or ratified by any gang leader, officer, or governing or policy-making person or authority, or by any agent, representative, or deputy of any such officer, person, or authority:
(1) with the intent to increase the gang's size, membership, prestige, dominance, or control in any geographical area; or
(2) with the intent to provide the gang with any advantage in, or any control or dominance over any criminal market sector, including but not limited to, the manufacture, delivery, or sale of controlled substances or cannabis; arson or arson-for-hire; traffic in stolen property or stolen credit cards; traffic in prostitution, obscenity, or pornography; or that involves robbery, burglary, or theft; or
(3) with the intent to exact revenge or retribution for the gang or any member of the gang; or
(4) with the intent to obstruct justice, or intimidate or eliminate any witness against the gang or any member of the gang; or
(5) with the intent to otherwise directly or indirectly cause any benefit, aggrandizement, gain, profit or other advantage whatsoever to or for the gang, its reputation, influence, or membership.
740 ILCS 147/10