Most New York DWI Charges are "Per Se" BAC based Charges
Most New York State DWI charges have an associated chemical test of blood or breath. The chemical testing of breath samples are behind the most common New York State DWI charges. Remember Driving While Intoxicated can be proven two ways: common law by observations and testing of your behavior and per se by a specific amount of alcohol in your body close or at time of driving.
There is a margin of error with any testing, especially scientific testing of samples. The question is what is an acceptable margin of error in NYS DWI Breath Testing?