O.C.G.A. § 5-5-1: Power of probate, superior, state, juvenile, State-wide Business, and City of Atlanta courts.

(a) The superior, state, and juvenile courts, the Georgia State-wide Business Court, and the City Court of Atlanta shall have power to correct errors and grant new trials in cases or collateral issues in any of the respective courts in such manner and under such rules as they may establish according to law and the usages and customs of courts.

(b) Probate courts shall have power to correct errors and grant new trials in civil cases provided for by Article 6 of Chapter 9 of Title 15 under such rules and procedures as apply to the superior courts.