The laws regarding driving under the influence (DUI) and breathalyzer tests can vary by jurisdiction, so it's essential to consult with a qualified legal professional for specific advice.
In most places, the law does not distinguish between "perfectly functioning alcoholics" and other individuals when it comes to DUI charges. If a person is pulled over by law enforcement and suspected of driving under the influence, they may be asked to take a breathalyzer test to measure their blood alcohol concentration (BAC).
Even if someone believes they can function well despite consuming alcohol, a breathalyzer test can show whether their BAC is above the legal limit for driving. It's worth noting that BAC levels can vary based on factors such as body weight, metabolism, and the amount of alcohol consumed. What might be "perfectly functioning" for one person could still put them over the legal limit for driving.
If a driver's BAC exceeds the legal limit, they can be arrested and charged with a DUI, regardless of how well they believe they can perform daily tasks.
To avoid any legal issues and ensure public safety, it's best to refrain from drinking and driving altogether. If someone has a concern about their alcohol use and its potential impact on their ability to drive safely, they should seek help from a healthcare professional or support group. Remember, it's crucial to prioritize safety on the roads for oneself and others.