O.C.G.A. 16-15-9 (2010)
16-15-9. Commission of offense admissible as evidence of existence of criminal street gang and criminal gang activity

The commission of any offense enumerated in paragraph (1) of Code Section 16-15-3 by any member or associate of a criminal street gang shall be admissible in any trial or proceeding for the purpose of proving the existence of the criminal street gang and criminal gang activity.