You go out for lunch with your wife, and you each drink two glasses of wine. As she rarely drinks, and you do so frequently, you agree it is better that you drive. While there is some logic to this, it is not as straightforward as you might think.
When the police stop you and ask you to blow into a Breathalyzer, they are not interested in how often you drink or how much you can consume before falling over. They are interested in your current blood alcohol content (BAC).
Alcohol tolerance does not affect your BAC
Having more drinking experience might mean you feel less tipsy than your wife, but it will not affect your BAC.
BAC is the ratio of alcohol to blood, so the more blood you have in your body, the less a given quantity would raise your index. The amount of blood you have depends on your size. It also depends on gender.
So, if you are built like the Hulk and your wife is small in stature like Dolly Parton, then consuming the same amount of alcohol may, in theory, give you a lower BAC than her.
The problem is, none of this is an exact science. Several factors affect your BAC, including how long ago you drank the alcohol, what you have eaten and if you have alcohol in your blood from the night before. Trying to second guess whether you are safe to drive is a recipe for disaster. If you are facing a DUI charge, then telling a judge that you thought you were OK will not help you. There are, however, a variety of defenses that may.