O.C.G.A. § 40–6-391(a)(2)

(a) A per­son shall not drive or be in actual phys­i­cal con­trol of any mov­ing vehi­cle while:

(2) Under the influ­ence of any drug to the extent that it is less safe for the per­son to drive.

Ele­ments of the charge:

The pros­e­cu­tor must prove beyond a rea­son­able doubt:

1. Per­son was dri­ving or had actual phys­i­cal con­trol of the vehicle;
2. Dri­ving with a con­tra­band (ille­gal for all pur­poses) sub­stance in driver’s system;
3. Per­son is less safe because of the quan­tity or con­cen­tra­tion of the drug in his sys­tem at the time of dri­ving; and
4. Per­son is inca­pable of dri­ving safely