Is there SCIENCE in Forensic Science?

Kentucky Department of Public Advocacy2014 Annual Conference

17 June 2014

Jay A. Siegel, PhDEmeritus Professor of Forensic Science -

Michigan State UniversityAdjunct Professor of Forensic Science – Indiana University Purdue University

Indianapolis

Validity of Methods of Analysis

DNA – methods of analysis proven to be valid: taken from medical science

Chemical identification – proven to be valid: used for years in analytical chemistry Drugs and toxicology Explosives and accelerants Paints, coatings, plastics, other materials

Pattern evidence - arose from police science. Scientific validity has not been established Beware validation by case work Not completely validated ≠ invalid!

Examples of Pattern Evidence

Firearms

Lands and grooves: class characteristics

Stria: individual characteristics

Fingerprints

Pattern type: class evidence

Minutia: individual chracteristics

Handwriting

Overall handwriting: class characteristics

Details of handwriting: Individual

characteristics

Bias in Forensic Science

Some types of bias

Situational – crime labs located in police departments

Cognitive – Examiner knows too much about the case

Confirmational – one examiner confirms results of another. 2nd examiner knew the results of the 1st

Confirmational Bias at Work: The Brandon Mayfield Case

The Case

Terrorist bombing in Madrid, Spain

Police recover partial fingerprint at scene, send photograph to FBI to develop suspects through IAFIS system.

Brandon Mayfield’s print comes back as 4th best hit

He had recently converted to Islam, wife was Egyptian

Suspicion fell on him and he is arrested

Brandon Mayfield

FBI examiner declares that Mayfield’s print

matches photograph of recovered print 2nd FBI examiner gets file including 1st

examiner report and confirms conclusions 3rd FBI examiner gets file including 1st and 2nd

examiner reports and confirms conclusions Mayfield retains independent fingerprint

expert, who obtains all FBI files. He confirms conclusions

The fingerprint examinations

Madrid police capture terrorist and confirm

fingerprint match FBI sends fingerprint team to Madrid. They

agree with Madrid PD and Mayfield is released. He sues federal government and is awarded

$4M

The fallout

P partial fingerprint lifted

from Madrid bombing

scene

The Fingerprints

Accreditation and Certification

Issues Accreditation Certification

Not mandatory Patchwork of

standards: many organizations offer, but the standards are all different

Not mandatory Patchwork of

organizations that offer certification

Not tied to a licensure so no revocation of ability to practice forensic science

Forensic Science Laboratory Reports

Problems

No standards Can be used as “evidence of the facts

therein” Many are little more than certificates of

analysis Not real scientific reports

Where do we go from here?

Role of the NAS report More research into how to validate

comparison techniques Clearly and unambiguously identify terms Develop standard, validated methods for

analysis Recognize and minimize bias Write scientific lab reports

National Commission on Forensic Science

Thank you for your attention

Questions?