In Forte v. State, 707 S.W.2d 89, 94-95(Tex.Crim.App. 1986) the court of criminal appeals was faced with a challenge to the amended statute, which for the first time defined "intoxication" as either loss of faculties or having an alcohol concentration of .10 or greater in the body. The court found this new per se definition of intoxication did not constitute a mandatory conclusive presumption, and its explanation sheds light on our case: To be sure, if the State relies upon the 0.10% definition of intoxication, then such proof will normally appear in the form of a chemical test showing the alcohol concentration in a defendant's body near the time of the offense. However, a conviction will not necessarily follow from the offer of such a test. First, the trier of fact must still be convinced beyond a reasonable doubt that the chemical test provides trustworthy evidence of alcohol concentration in a defendant's breath, blood or urine. Second, the jury must still be convinced beyond a reasonable doubt that an inference can be made from the results of the chemical test that the defendant had a 0.10% alcohol concentration in his body at the time of the offense. Nothing prevents a defendant from challenging the validity of the test itself by attacking the reliability of the machine or the qualifications of the operator. Nor does anything prevent a defendant from arguing that his alcohol concentration increased from the time of the arrest to the time of testing. In no way does Article 6701l--1, supra, encourage a jury to ignore such defensive evidence on the issue of intoxication in favor of a presumption, whether mandatory or permissive. Forte, 707 S.W.2d at 94-95.