DRIVING WHILE IMPAIRED?
Alcohol elimination
A Wilkes County man was sentenced to 33 years in prison without possibility of parole for the deaths of Harley and Helen Carter. The man, Ricky D. Norman was driving a truck traveling south on Old U.S. 21, when he collided with a car driven by the Carters. Not only Norman admitted that he was speeding, he also had been drinking and had cocaine in his system at the time of the crash. As a matter of fact he had been convicted of DUI three times and had a fourth DUI charge pending at the time of the accident. What caught my eye was the fact that the prosecution and defense experts differed as to whether he was legally drunk.
The trial lasted a week and much of the trial testimony involved experts who had opposing views about how intoxicated Norman was and how far he was from the intersection when Harley Carter pulled out in front of him. How could two experts do not agree on the alcohol level Norman had? Well, Norman had two broken ribs, a collapsed lung, a broken pelvis, a broken sternum, two broken bones in his left forearm and a broken right heel, and was taken to Hugh Chatham Memorial Hospital. Due to his injuries, I guess, his blood was tested two hours after the accident and the test results showed Norman’s blood alcohol content was 0.03.
Paul Glover, an expert from the Forensic Tests for Alcohol Branch of the N.C. Department of Health and Human Services, testified Thursday that Norman’s blood alcohol content at the time of the wreck would have been 0.08. Glover used a technique called “retrograde extrapolation”. He said he determined a rate at which Norman’s body was eliminating alcohol, and calculated backward to determine the blood-alcohol level at the time of the wreck. A defense expert, Andrew Mason, told jurors that Norman’s blood-alcohol content would have fallen within a range of 0.05 to 0.09 at the time of the crash. For him, Glover’s determination is not scientifically supported, partially because people don’t eliminate alcohol at constant rates.
Before receiving his sentence, Norman said he was convicted because of his criminal record and not because of his responsibility for the fatal crash. He said he felt it was okay to drive after drinking four beers, that it wouldn’t bring him up to the legal limit which, in North Carolina, is 0.08.
I would love to hear from our faculty and students about how uncertain it would be to determine alcohol elimination rate. Are there any variables, maybe personal variables that need to be taken into account?
Click here for more details on this story.
August 11th, 2009 at 4:38 pm
It seems the jury decided that the range 0.05 to 0.09 did include 0.08 and 0.09 (to give the defense expert credit). Given the circumstances, and the fact that cocaine was also found in the bloodstream (not sure if it was cocaine, a mix of cocaine and benzoylecgonine, or just benzoylecgonine), it does not seem out of sorts here to expect a quick conviction in this case. Whether the prosecution proved the blood test beyond a reasonable doubt - that is unlikely… but it seems that they nailed the defendant on many other issues here that secured a guilty verdict.
My question to others - would you vote not guilty solely based on the expert testimony which predicted a 60% chance that the defendant was not drunk while another said that he was “100%” drunk?
August 13th, 2009 at 1:20 pm
Retrograde extrapolation should be illegal to even be presented in court as scientific evidence. Not only can no one prove the rate of elimination of alcohol of each individual person, it makes many leaps in logic to claim a false conclusion. Having this pseudo science in court is a heinous act and does not get to the heart of the matter. Justice! For a prosecutor to even allow this to be a leg of his case is underhanded. To then even try to mitigate the damage by saying you have something with a 60% margin of error is even worse than the pseudo science itself.
As a judge I would only allow information pertaining to the actual case: i.e. what was this man’s, before me, actual BAC.
Too often do the police refuse to investigate an accident once they can remotely prove alcohol ws involved in the accident.
Not only would I vote not guilty, but I would seek to penalize the prosecution for presenting retrograde extrapolation as evidence of any sort.
August 31st, 2009 at 1:00 pm
Retrograde extrapolation, with the appropriate caveats, is good, defensible science. You can’t nail down the exact elimination rate, but taking into consideration body weight, height, the blood alcohol level at the time of the test, the passage of time, etc. you can make a pretty good guess at the alcohol level at the time of driving. You can generate a spectrum of values within which most humans would fall. The chronic alcoholic would not fall within these values, but in that case the values would work in the alcoholic’s favor, and not against him/her.
October 1st, 2009 at 6:57 am
I noted that the charge was driving while impaired, as opposed to driving with unlawful blood alcohol level (DWI or DUI vs DUBAL). For conviction under DWI/DUI statutes, there often does not require absolute proof that a BAL of ≥ 0.08% was present at the time of accident; therefore, a conviction is possible even if a BAL didn’t meet the DUBAL requirements (at least this is the case under Florida law). The fact is that alcohol metabolism proceeds at a zero order rate and blood tests two hours apart can determine an elimination rate with some accuracy; therefore, the science of retrograde analysis is valid, but the analyst must list the conclusion as a set of possible values for the BAL at time of accident. I would definitely convict on a lesser charge of negligent homicide due to the speed factor; I’m a bit uncomfortable with the alcohol and cocaine data and would want a full accounting of methodology before convicting for any murder charge.
October 6th, 2009 at 2:14 pm
I wonder if they tested for a cocaethylene level? This would impact the level of intoxication the subject was under at the time of the cash. It could also shed some light on the alcohol levels as well, though I don’t know off hand the ratio of alcohol and cocaine ingested to cocaethylene levels, it could provide some additional information. I my state the cocaine would have been enough to have a DUI. With an explanation of the equation retrograde analysis is used in our court, though thankfully I haven’t yet had to use it.
On another note if his blood was drawn two hours after the accident and was positive for cocaine, not a metabolite, he must have been ingesting it while he was driving, not safe driving at all.
October 9th, 2009 at 11:58 pm
What I don’t understand is how easly a juror is persuaded just because someone potentially was a .08. It seems that prosecutors more and more these days are only able to rely on one piece of evidence - the BAC and even that now is becoming very questionable.
October 12th, 2009 at 1:22 pm
BAC analysis and retrograde analysis have been tested and reviewed for decades it is one of the most studied analysis in toxicology We have know driving and driving are dangerous for over 100 years and it been illegal almost that long as well. In most cases you have to do something to get pulled over in the first place, usually it unsafe driving, so it isn’t just someone who happens to have a BAC over the legal limit driving. For anyone how thinks a “little” drinking an driving is OK, I have a few hundred thousand dead people I like you to meet. That not junk science that fact. Funny how everybody known this but the DUI lawyers.