A Texas man who was sentenced to four years in prison after his fourth driving-while-intoxicated conviction has come up with a novel appeal.

Ralph Alfred Friesenhahn of San Antonio is trying to overturn his conviction by arguing that Texas' .08 blood-alcohol limit discriminates against alcoholics.

Here's his case in a nutshell: the .08 limit does not factor in the higher tolerances that alcoholics have. He argues that the “protected class of alcoholics” — those with high tolerances — can be prosecuted even without the state having to prove that they were impaired by alcohol to the point where they presented a danger to other drivers.

And here's Friesenhahn story: He was jailed after his fourth DWI in 2016. He was arrested after his car rolled over on a rural road. A blood test showed he had an alcohol concentration of 0.29 — more than 3½ times the legal limit.

His lawyer, Gina Jones, moved to throw out Friesenhahn’s indictment, arguing that the legal driving limit discriminated against alcoholics, the American Statesman wrote.

After Friesenhahn was convicted of felony DWI because of his prior alcohol-related convictions, Jones made the same argument on appeal, leading to Friday’s 3rd Court of Appeals decision upholding Robison’s ruling. Jones has not yet responded to an interview request.

Sammy McCrary, chief of the felony division for the Comal County criminal district attorney’s office, said it is ridiculous and misleading to suggest that the law treats alcoholics differently.

“You’re not being punished for being an alcoholic. It’s the driving that’s the problem,” McCrary said. “It’s making the decision to get into a 3,000-pound vehicle … after drinking.”

The Austin-based 3rd Court of Appeals didn't go for the novel appeal, saying in a ruling that state law does not unfairly single out alcoholics because it applies equally to all drivers (including hardcore alcoholics). No exceptions.

Friesenhahn not only failed to present evidence that alcoholics are a protected class under the Americans With Disabilities Act or other federal law, he also failed to prove that the law treats alcoholics differently than other DWI defendants, said the opinion by Justice Cindy Olson Bourland.

“Instead, he argues that they ‘should’ be treated differently … and thus fails to establish an equal-protection violation,” Bourland wrote.