A Paulding county lawyer knows there is no legislation in the State of Georgia and establishes a per se impairment level for various controlled substances. Other states like Virginia and Nevada have a per se impairment level for controlled substances such as marijuana. This may become even more popular or common as more states begin to legalize marijuana. There will become a need for experts on this type of testing in states like Colorado and Washington where they have legalize marijuana. In head v. State 303 Ga. App. 475, 2010, after a stipulated bench trial based upon the transcript held upon his demurrer head was convicted of DUI of any drug to the extent that it is less safe for him to drive, in violation OCGA 40-6-391(A) and driving with a controlled substance in the blood, in violation OCGA 40-6-3 91A6. His DUI drugs per se conviction merged with the DUI less safe conviction. In his appeal had contended that the evidence was insufficient to support his DUI less safe conviction and that OCGA 40-6-391(a)(6) violates the equal protection clause of the 14th amendment to the United States Constitution. OCGA 40--6-391(a)(3) includes the crime of DUI driving under the influence of any glue, aerosol, or other toxic vapor to the extent that it is less safe for the person to drive. To prove such cases, the State will need expert testimony to establish quantitative level for such chemical in sufficient quantities to use less safe driving and not just the mere presence of toxic vapors in the suspect blood. No charts or per se limits exist for toxic vapors, so no scientific reliable evidence should be able to convict a defendant. Contact a Paulding County DUI lawyer if charged with driving under the influence of glue or aerosol.