Forensic Toxicology & Drug Katherine Sato Office of the Ohio - - PowerPoint PPT Presentation
Forensic Toxicology & Drug Katherine Sato Office of the Ohio Public Chemistry for Defense Attorneys Defender Introduction Forensic Toxicology Outline of Alcohol/OVI Testing Presentation Drug Field Testing Drug Chemistry for the
Katherine Sato Office of the Ohio Public Defender
Introduction Forensic Toxicology Alcohol/OVI Testing Drug Field Testing Drug Chemistry for the Defense
The application of analytical techniques in a legal setting for the purpose of identification of unknown chemical substances
Employs the analytical techniques of chemistry for the detection of drugs, toxins, and/or pharmaceuticals in biological samples
Both the overt effects of biologically active chemicals and the mechanism by which these chemicals interact with each other and biological targets
Pharmacokinetics
Pharmacogenetics
Right to confrontation May need to circumscribe an expert’s testimony Cross-discipline fields → may need multiple experts
SCOTUS: defendants have a right to confront laboratory analysts Held: 1. Analysts’ certificates of analysis are testimonial statements; 2. Analysts are not removed from coverage
3. Defendant’s ability to subpoena analyst did not obviate State’s obligation to produce analyst for cross-examination
“Nor is it evident that what respondent calls ‘neutral scientific testing’ is as neutral or as reliable as respondent suggests. Forensic evidence is not uniquely immune from the risk of manipulation. According to a recent study conducted under the auspices of the National Academy of Sciences, ‘[t]he majority of [laboratories producing forensic evidence] are administered by law enforcement agencies, such as police departments, where the laboratory administrator reports to the head of the agency.’ * * * And ‘[b]ecause forensic scientists often are driven in their work by a need to answer a particular question related to the issues of a particular case, they sometimes face pressure to sacrifice appropriate methodology for the sake of expediency.’ A forensic analyst responding to a request from a law enforcement official may feel pressure—or have an incentive—to alter the evidence in a manner favorable to the prosecution.”
In any criminal prosecution, a laboratory report from BCI (or other accredited lab) stating:
analyzed;
identity of the substance;
substance; and
Is “prima facie evidence” of the content, identity, and weight of the substance.
When the state has complied with its
defendant’s failure to use the procedures of R.C. 2925.51(C) to demand that a laboratory analyst testify constitutes a waiver of the
analyst at trial and allows the analyst’s report to be admitted as prima facie evidence of the test results.
“We hold that surrogate testimony * * * does not meet the constitutional requirement. The accused’s right is to be confronted with the analyst who made the certification, unless that analyst is unavailable at trial, and the accused had an opportunity, pretrial, to cross-examine that particular scientist.” “SLD analysts use gas chromatograph machines to determine BAC levels. Operation of the machines requires specialized knowledge and training. Several steps are involved in the gas chromatograph process, and human error can occur at each step.”
nonscientists
claim to identify whether a person was on PCP vs. heroin
their observations
drugs affect the human body
that occur within a living organism
substances) and catabolism (the breakdown
inactive
impairment (not psychoactive)
determine how quickly individual metabolizes specific drug) if when the person took the drug is important
Half-Life
Metabolism of Cocaine
Can determine impairment Varies less by individuals More invasive
Cannot determine impairment Individual variation Less invasive, more common
properly stored
lot of sugar and yeast in the urine, could change to alcohol after it leaves the body while stored)
AG’s Guidelines
actively growing hair will sequester some of the drug
part of hair indefinitely
continue down the hair as it grows
Standardized field sobriety tests Intoxilyzers
Three tests used in combination to determine intoxication: 1. Horizontal Gaze Nystagmus (HGN) – involuntary eye movement 2. Walk-and-Turn (WAT) – divided attention activity 3. One-Legged Stand – divided attention activity Should only be used for alcohol, not proper for marijuana or any other drugs
National Highway Traffic Safety Administration (NHTSA) found that, in determining whether a subject’s BAC was .10 or above:
accurate
accurate
were 80% accurate One study found 24% false positive results
the lungs
estimated from breath alcohol concentration (BrAC) using a generalized ratio of BAC:BrAC = 2100:1
to your client
difference between BAC of .079 and .08
One breath sample Calibration Temperature Non-selective Sample destroyed Assumes partition ratio of 2100:1
Calibration information All solutions used to calibrate the machine Margin of error of all solutions used to calibrate the machine Maintenance of the instrument
[OVI], the court may admit evidence on the concentration of alcohol * * * in the defendant’s * * * breath * * * at the time
substance withdrawn within three hours of the time of the alleged violation.”
this section shall be analyzed in accordance with methods approved by the director of health * * *”
Because the legislature provided for the admissibility of intoxilyzer tests if analyzed in accordance with methods approved by the director of ODH, an accused may not present expert testimony attacking the general scientific reliability of approved test instruments.
The approval of a breath-analyzer machine by the director of the Ohio Department of Health does not preclude an accused from challenging the accuracy, competence, admissibility, relevance, authenticity, or credibility of a specific test result or whether the specific machine used to test the accused operated properly at the time of the test.
Can someone reliably estimate the amount of alcohol ingested from a single measurement of a person’s blood alcohol concentration (BAC)?
Blood-Alcohol Curve
Widmark Formula
“A retrograde extrapolation calculation based on a single breath test, and when many of the factors necessary to determine whether the defendant was in the elimination phase are unknown, is insufficient to provide a reliable calculation and invites the jury to determine guilt on an improper basis. Based on the specific circumstances presented in this case, we believe that the prejudicial effect of the retrograde extrapolation calculation substantially outweighed its probative value and that the trial court abused its discretion in admitting it.”
The following factors are relevant to achieving a sufficiently reliable retrograde extrapolation calculation: (1) gender, (2) weight, (3) age, (4) height, (5) mental state, (6) the type and amount of food in the stomach, (7) type and amount of alcohol consumed, (8) when the last alcoholic drink was consumed, (9) drinking pattern at the relevant time, (10) elapsed time between the first and last drink consumed, (11) time elapsed between the last drink consumed and the blood draw, (12) the number of samples taken, (13) the length of time between the
absorption rate, and (15) the average elimination rate.
Drug Color Test Kits
Drug Color Test Kits in the News
confirmatory testing
they wait
conviction (compared to the immediate reward of pleading and getting out of jail)
show no controlled substances present
about false positive rates
Types of Laboratory Testing Potential Errors in Testing SWGDRUG Recommendations Accreditation Process Documents to Request
Gas Chromatography/ Mass Spectrometry (GC/MS) Liquid Chromatography/ Mass Spectrometry (LS/MS) Thin Layer Chromatography (TLC) Color Tests
Gas Chromatography/ Mass Spectrometry (GC/MS)
Liquid Chromatography/ Mass Spectrometry (LS/MS)
Thin Layer Chromatography (TLC)
widely used database of organic compounds
compounds
get the molecule’s distinctive ‘mass spectra,’ which looks like a barcode and functions like a fingerprint.”
NIST Mass Spectral Library
2009 NAS Report
“Some laboratories might mention the tests that were conducted, but in most cases the spectra, chromatograms, and other evidence of the analysis and the chemist’s notes are not submitted. Likewise, possible sources of error and statistical data are not commonly
reporting is often inadequate, because it may not provide enough detail to enable a peer or other courtroom participant to understand and, if needed, question the sampling scheme, process(es) of analysis, or interpretation.” (135)
PCAST Report
“One analysis estimated that at least fifty major laboratories reported fraud by analysts, evidence destruction, failed proficiency tests, misrepresenting findings in testimony, or tampering with drugs between 2005 and 2011. Twenty-eight of these labs were nationally accredited.” (33, fn60)
dropped-after-massive-drug-lab-scandal-923957827606
Incompetence/Negligence
Fabrication/Deception
enforcement Bias
procedures used Incomplete/Misleading Reports
carry over from previous samples
amount of sample
into several samples
SWGDRUG Recommendations
Specific Provisions of SWGDRUG
into different sections, and take notes (basically an audit)
rmis ission from the lab technicians to give them files
using individual inspectors’ notes
whether written procedures in place, whether there are quality control procedures
(international organization)
(suspect)
Laboratory Accreditation Board
1. Preliminary Assessment Report
procedures so others can replicate process, failure to record key information, failure to perform tests, failure to follow lab manuals and procedures)
2. Corrective Action Request (CAR)
memo form signed and submitted by section chief)
3. Final Assessment Report
4. Laboratory Information Management System (LIMS) Printout
conclusion from the technician assigned to the case
misplaced for a while 5. Quality Manual
quality manual (if not, in violation of accreditation)
the lab has prescribed for themselves
6. Nonconformity Reports
disagree (e.g., technician A finds a match, technician B finds it inconclusive, supervisor rules it a match)
meaning of the report
7. Root Cause Analysis (RCA)
to make a recommendation as to how to resolve the problem in the future
Katherine Sato Assistant State Public Defender, Juvenile Department katherine.sato@opd.ohio.gov