Saturday, April 23, 2011

Dr. DUI explains the silliness of the California Supreme Court in the landmark DUI Case People v. McNeal (1)

Dr. DUI explains the silliness of the California Supreme Court in the landmark DUI Case People v. McNeal (1)

Dr. DUI explains the silliness of the California Supreme Court in the landmark DUI Case People v. McNeal

by Okorie Okorocha on Saturday, April 23, 2011 at 7:25pm
The conversion from breath alcohol to blood alcohol is based on the chemistry principle of ‘Henry's law,’ which holds that there is ‘a constant ratio between the concentration of alcohol in the blood and the concentration of alcohol in the alveolar air of the lungs.’” People v. McNeal (2009) 46 Cal.4th 1183, 1191.
The use of Henry’s law here is a bit of a stretch. William Henry was a scientist in the very early 1800s and did not know what an Alveolus was.
Think about it for a second!!!
Here is what Henry's law says:
C=Khp
Henry's law can be put into mathematical terms (at constant temperature) as
where p is the partial pressure of the solute in the gas above the solution, c is the concentration of the solute and kH is a constant with the dimensions of pressure divided by concentration.[1] The constant, known as the Henry's law constant, depends on the solute, the solvent and the temperature.
Some values for kH for gases dissolved in water at 298 K include:
oxygen (O2) : 769.2 L·atm/molcarbon dioxide (CO2) : 29.4 L·atm/molhydrogen (H2) : 1282.1 L·atm/mol


  • David so what are the variables the Court did not consider?
    16 hours ago ·
  • Kenton What was the holding? Is p v Bransford impacted?
    9 hours ago ·
  • Okorie Okorocha Bransford did not allow the partition ratio variability evidence on the 23152B Count or the Count that say you cannot be over .08 or for the non-DUI nerds, this means evidence that breath does not accurately reflect blood levels, but this case changed the law to allow this evidence for the 23152A count which just says you cannot be "impaired" regardless of BAC. Very Confusing.
    7 hours ago ·
  • Okorie Okorocha Hi David Hicks, I could write a whole book on this. But, breath results are published/determined as grams of alcohol per 210,000ML or breath, which is 2100 times blood results of grams per 100 ML of blood. This 2100 ratio was decided by committee and was never proven and is not true because the ratio is always changing. Also, BAC of breath grams per 210,000ml or for blood, grams per 100 ml is called a percentage. This is grams or MASS over milliliters or Volume. Percentage would really be mass over mass or volume over volume, so that is rubbish.