Yet, all of these subjects were of the same weight and were given identical doses of ethanol and water. Bear these scientific facts in mind when you use these charts. To use the chart, find your body weight and read across to the number of drinks consumed. The resulting number represents your alcohol concentration, with allowance for the absorption and elimination of alcohol during the time since drinking began. You can also use the chart to learn how many drinks it would take to reach a particular test result.
Alcohol is absorbed and eliminated over time.
The rate of absorption is not really predictable, and varies among people and due to other factors, such as whether there is food in the stomach. The curve defense is based on this fact. If a driver is stopped and arrested while his or her alcohol concentration is rising, the test result probably will be higher than the alcohol concentration at the time of driving. To be able to determine whether it is more likely that the driver was absorbing or eliminating alcohol when stopped, the first fact that need to be known is when the person stopped drinking. Without that fact, any assumption concerning the person's status as absorbing or eliminating alcohol at the time is nothing but speculation.