Even though Joseph Schwab only had caffeine in his system at the time he was pulled over, he still faces a DUI charge.
The 36-year-old California man was driving home from work in August 2015 when an alcohol beverage control agent stopped him, KCRA reports.
The agent said Schwab was driving erratically, which made her think he was under the influence of drugs.
According to KCRA, a field sobriety test revealed dilated pupils.
Experts say that though caffeine is technically a drug, it's not often associated with impaired driving -- as a matter of fact, it often helps with driving.
Schwab's lawyers told KCRA the charge comes as a complete shock.
Prosecutors plan to move forward with the case, though, alleging that Schwab was under the influence of a drug they don't usually screen for.
"This is a case without a blood result, right, so it makes it a very difficult challenge to prove in court to not have the blood result," Solano County District Attorney Krishna Abrams told KCRA.
Schwab said that the charge has seriously hurt him financially, and his reputation has also taken a hit.
"Looks like I'm undependable," he told KCRA. "And when you tell this type of story to somebody, they are naturally not going to believe you."
Since driving under the influence of caffeine is not a crime, Shwab's attorney is asking for charges to be dismissed.
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