Here is why you should retest:

Even though alcohol testing of blood via head space gas chromatography is very accurate, it isn't perfect. As of 2015, laboratories accredited by ASCLD/LAB (now ANAB) are required to report their uncertainty of measurement for each type of test. By comparing lab results from two different labs and applying statistics, one can determine if the two results corroborate or not.


Above is a comparison graph that I provide free of charge if the client also provides me with the prosecution's results. In this particular case, there is only a 4.27% chance that the results corroborate. Since the corroboration is less than 5.00%, the results are considered noncorroborative. But which one is correct? Assuming no other extenuating circumstances, it is scientifically impossible to tell which one is correct. The result? Both results should be excluded.