1. Constructing Expertise The Cultures of Expert Witnessing

2. Widespread Use of Expert Witnessing in U.S. Law By early 20 th century most cases used some form of specialized testimony Average American juror has no education beyond high school Adversarial process of “deconstruction”

3. Adversarial Process Scientific claims made in legal setting are bound to specific notions of cause, blame, and responsibility Diametrically opposed witnesses may give false impression that scientific opinion is divided 50/50

4. Advantage of Adversarial Process Can catch outright lies Can unravel shaky consensus and expose untested presumptions Can educate public

5. Problems with Expert Witnessing Can distort legal process Testimony framed to win Aggrandizement Commodification Mechanisms for establishing credibility are not same as mechanisms for establishing scientific competence

6. “Even where facts cannot be established with certainty Anglo- American courts typically make definitive findings of fact and treat them as certain….” Martin Shapiro in Jasanoff, 45

7. “Courtroom science” Example X-rays Were they admissible as evidence? As evidence of what?

8. “There is no evidence that the photograph actually portrayed and represented the object pictured.” Defendant’s attorney in first X-ray case

9. Judge in first X-ray case

10. “Courtroom science” Example: DNA testing Rapid diffusion of testing in late 1980s Variation between private labs No peer review - bypasses normal process of validation

11. What does DNA “fingerprinting” teach us? Early consensus Taken for granted assumptions Limits of knowledge Methodological variation Deconstruction through adversarial legal process

12. BOUNDARY WORK Normative commitments Shared lines drawn between good/bad valid/invalidcredible/incredible

13. “There is a bias toward maintaining the institutional authority of science even in these orgies of deconstruction…” Jasanoff, 53