Add to ORKGDuring the past several years in this state it has not been compulsory for persons under arrest to submit to chemical tests to determine the concentration of alcohol in their body fluids. Generally, however, law enforcement officers have asked arrested motorists who showed signs of intoxication to submit to a blood or urine test. Charges of driving while intoxicated have usually been filed if the alcohol concentration of the blood was 150 mg. per 100 cc. or over. A sufficient number of persons have been tested under this routine to give a cross section of the drivers on the highways of this state. From the records of this laboratory for a two year period just ended we have summarized the results of blood tests on 402 drivers in central Iowa...