What is the “legal limit” in New Hampshire?
New Hampshire defines legal impairment in two alternative ways. Under one definition, a driver is per se impaired if he has an alcohol concentration of 0.08 or greater at the time he was driving. A driver who is under 21 is per se impaired if he has an alcohol concentration of .02 or greater. A driver with a CDL license who is driving a commercial vehicle is per se impaired if he has an alcohol concentration of 0.04. Under the second definition, a driver is DWI if he is actually impaired by alcohol and/or drugs to any perceptible degree. Under this definition, the driver’s alcohol concentration is merely circumstantial evidence of actual impairment. An alcohol concentration of 0.08 or greater is prima facie evidence of impairment. This means that if the State proves that the driver had an alcohol concentration of 0.08 or greater at the time he was driving, that is sufficient to prove impairment. However, it is not conclusive evidence of impairment. An alcohol concentration of 0.03 or l
