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By what standards do we practice our discipline?. Keith Inman Forensic Analytical Specialties, Inc. We must understand what this is about, or we will make mistakes!. They can do pretty much anything. The public thinks we can, too. Forensic Science. As a discipline
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By what standards do we practice our discipline? Keith Inman Forensic Analytical Specialties, Inc.
We must understand what this is about, or we will make mistakes!
They can do pretty much anything. The public thinks we can, too.
Forensic Science • As a discipline • Someone asks us to do something • Someone gives us the material to do it on • We have no control over how our results are used
How did we get here? In the beginning, religion ruled everything in the Western world, including law and science!
Then each grew into its own kingdom… And claimed rights and dominion over the other two
Science over religion If we find the answer to that (why we and the universe exist), it would be the ultimate triumph of human reason - for then we would know the mind of God Stephen Hawking, A Brief History of Time
Religion over science Galileo, who was not in the best of health, was summoned to Rome, found to be vehemently suspected of heresy, and eventually condemned to house arrest, for life. He was also forbidden to publish. By the standards of the time he had got off rather lightly.
Law over science DAUBERT, et al. v. MERRELL DOW PHARMACEUTICALS, INC. Faced with a proffer of expert scientific testimony under Rule 702, the trial judge, pursuant to Rule 104(a), must make a preliminary assessment of whether the testimony's underlying reasoning or methodology is scientifically valid and properly can be applied to the facts at issue
What kind of science are we? Science is an organized body of knowledge, or systematic gathering and categorizing of knowledge Applied science is the art or science of applying scientific knowledge to practical problems The scientific method is a process of investigation involving observation and theory to test hypotheses
What kind of science are we? Science is an organized body of knowledge, or systematic gathering and categorizing of knowledge Color is as variable as the spectrum, but clear quartz is by far the most common color *Luster is glassy to vitreous as crystals, while cryptocrystalline forms are usually waxy to dull but can be vitreous. *Transparency: Crystals are transparent to translucent, cryptocrystalline forms can be translucent or opaque. *Crystal System is trigonal; 3 2. *Crystal Habits are again widely variable but the most common habit is hexagonal prisms terminated with a six sided pyramid (actually two rhombohedrons). *Cleavage is very weak in three directions (rhombohedral). *Fracture is conchoidal. *Hardness is 7, less in cryptocrystalline forms. *Specific Gravity is 2.65 or less if cryptocrystalline. (average)
What kind of science are we? Applied science is the art or science of applying scientific knowledge to practical problems
Applied science • What is it? (Identity) • Where did it come from? (source/contact) • How did it get there? (reconstruction)
Applied science • Most applied sciences have much of the problem “controlled” • Someone else initiates the request • Specimens from known source, collected in controlled fashion • Problem clearly defined • Answers passed to someone else for decision/action
What kind of science are we? The scientific method is a process of investigation involving observation and theory to test hypotheses • Hypotheses • Cast off from bloody instrument • Blunt force impact
Scientific Method • The scientific method is a search for knowledge using a system of inquiry • Always some pre-existing knowledge of problem and answer • There are always assumptions • Hypothesis are proposed about the answer, as well as a meaningful competing hypothesis • Tests must differentiate between hypotheses
Scientific Method • Well-designed hypotheses and tests lead to easily interpreted results that are useful • Evaluation of results done in context of original hypotheses, and reveal something new or unknown • Assumptions assist in evaluating the usefulness of the answer
Current Paradigm • Divisible matter (fracture of materials) • Transfer (Locard Exchange Principle) • Identification (placing objects in a class) • Individualization (narrowing the class to one) • Association (linking an object with a crime scene • Reconstruction (sequencing past events)
Common Practice of Forensic Science • Trend is to adopt exclusively the clinical/applied science model • Someone provides specific problem or question, without context or supplemental information • Know some, but not all, of paradigm of forensic science
Common Practice of Forensic Science • Common requests: • Detective - Please find the suspect’s blood on these shoes • DA - Is this father’s semen on his daughter’s panties? • Defense Atty - Is there doggie DNA on this vaginal swab?
Common Practice of Forensic Science • Is this felon’s DNA on this handgun? • Can you have it for court tomorrow? • Can you examine these 165 stains in a trail from the crime scene?
Common Practice of Forensic Science • Reaction: • Most common questions re-occur, so detailed protocols/SOP’s • Labs focus on running the protocols correctly • Hire and train people who can run protocols, not pose hypotheses or evaluate results for multiple hypotheses
Common Practice of Forensic Science • Result: • Reports often leave inferences/conclusions to someone else • Failures occur, and are conceptual, analytical, or malicious
Common Practice of Academic Involvement • Are by nature indoctrinated in scientific method
Common Practice of Academic Involvement • Frequently asked: • Is what the lab said, actually possible? • Could this (unusual) substance be present? • Where does this come from? • Is this (public lab result) based on science?
Common Practice of Academic Involvement • Protocols normally developed for research • Rigorous QC absent (no proficiency testing) • Conditions for research tightly controlled; not for evidence • Rarely know context of case • Completely unaware of paradigm of forensic science • Unaware of ethical requirements of discipline
Common Practice of Academic Involvement • Reaction • I know science, I’ll show them! • Will pose hypotheses, but often not more than one • May develop tests specific to the situation
Common Practice of Academic Involvement • Result • Frequently do not appreciate the complexity of human interactions, and how it effects evidence • May not know real limitations of their tests • Inferences naïve and incomplete
Returning to the law…. • Law limits introduction scientific evidence that is either: • Generally accepted • Determined by judge to be sound • What are scientists willing to do under these restrictions? • Report results • Attack results (or science)
Robert K. Merton On the Shoulders of Giants • Assertion • Attack • Dig in • Polemic Polemics are solved by clear, open, free, communication: pretenders fade away
Why is this important? • Self-correcting sociology of science thwarted • Lawyers, judges, juries will fill in the gaps we leave
What constitutes competent practice? • Know where you are in the paradigm - (forensic part) • Posemultiple reasonable hypotheses and decide on appropriate tests (scientific method part) • Run tests properly (applied science part) • Draw proper and limited inferences (forensic science!)
If you don’t ask the right question, You will not get the right answer, Regardless of the brilliance of your analysis!!!
More likely to ask the proper, relevant question if: • Get the problem • Get the story (context and history of the evidence) • Articulate assumptions • Bias occurs when someone else is allowed to ask the question!
Ethics of the profession Scientific and Technical skills Court What constitutes competent practice?
Acknowledgments Dr. Norah Rudin FASI staff Students at CSUH Dr. Daniel Krane