Susan Haack
Trials & tribulations:
science in the courts
“I should like to know” [asked Mr. Chi-
chely] “how a coroner is to judge of evi-
dence if he has not had a legal training?»
“In my opinion,” said Lydgate, “legal
training only makes a man more incompe-
tent in questions that require knowledge
of another kind. People talk about evi-
dence as if it could really be weighed in
scales by a blind Justice. No man can judge
what is good evidence on any particular
subject unless he knows that subject well.
A lawyer is no better than an old woman
at a post-mortem examination. How is he
to know the action of a poison? You might
as well say that scanning verse will teach
you to scan the potato crops.”
–George Eliot, Middlemarch (1872)
Justice requires just laws, bien sûr, et
just administration of those laws; but it
also requires factual truth. And in deter-
Susan Haack is Cooper Senior Scholar in Arts and
les sciences, professor of philosophy, and professor of
law at the University of Miami. Internationally
known for her work in philosophy of logic, episte-
mology, pragmatism, philosophy of science, et
the law of scienti½c testimony, Haack is the author
of several books, most recently “Manifesto of a
Passionate Moderate” (1998) and “Defending
Science–Within Reason: Between Scientism and
Cynicism” (2003).
© 2003 by Susan Haack
54
Dædalus Fall 2003
mining factual truth, in both criminal
and civil cases, courts very often need
to call on scientists: on toxicologists and
tool-mark examiners, epidemiologists
and engineers, serologists and psychia-
trists, experts on pcbs and experts on
paternity, experts on rape trauma syn-
drome and experts on respiratory disor-
ders, experts on blood, on bugs, on bul-
lets, on battered women, etc.. Pour, as sci-
ence has grown, so too has the legal
system’s dependence on scienti½c evi-
dence; it has been estimated that by 1990
autour 70 percent of cases in the United
States involved expert testimony, most
of it scienti½c. Such testimony can be a
powerful tool for justice; but it can also
be a powerful source of confusion–not
to mention opportunities for oppor-
tunism.
Who could have imagined, when dna
was ½rst identi½ed as the genetic materi-
al half a century ago, that dna analysis
would by now have come to play so large
a role in the criminal justice system, et
in the public perception of the law?
Even twenty years ago, forensic scien-
tists could tell only whether a blood
sample was animal or human, male or
female, et, if human, of what type (le
least common blood type being found in
3 pour cent, and the commonest in 43 par-
cent, of the U.S. population). Alors, dans
the mid-1980s, dna ‘½ngerprinting’
made vastly more accurate identi½cation
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possible, to probabilities of the order of
a billion to one; and by now new tech-
niques have made it possible to amplify
and test the tiniest samples.
At ½rst, such evidence was strenuously
contested in court; but as its solidity,
and its power to enable justice, devenu
unmistakable, the ‘dna wars’ gradually
died down. By the spring of 2002, dna
testing had exonerated more than a hun-
dred prisoners, including a signi½cant
number on death row, and helped con-
vict numerous rapists and murderers. Dans
at least one instance, it both exonerated
and convicted the same person: after
serving nearly eleven years of a twenty-
½ve-to-½fty-year sentence for rape, Kerry
Kotler was released in 1992 when newly
conducted dna tests established his in-
nocence; less than three years after his
release, he was charged with another
rape, and this time convicted on the ba-
sis of dna analysis identifying him as
the perpetrator.
Even so, dna evidence can present
problems of its own: police of½cers and
forensic technicians make mistakes–
and have been known deliberately to fal-
sify or misrepresent evidence; juries may
misconstrue the signi½cance of expert
testimony about the probability of a ran-
dom match with the defendant, or of in-
formation about the likelihood that a
sample was mishandled–and attorneys
have been known to contribute to such
misunderstandings; criminals devise
devious ways to circumvent dna iden-
ti½cation–and at least one prisoner, ap-
parently hoping to exploit the potential
for confusion, has petitioned for a dna
test that, as he must have anticipated,
con½rmed his guilt.
And who could have imagined, quand
Hugo Münsterberg urged in his On the
Witness Stand: Essays on Psychology and
Crime (1908) that the law avail itself of
the work of experimental psychologists
on the reliability of memory, perception,
and eyewitness testimony, that less
than half a century later psychological
evidence would play a signi½cant role
in such landmark constitutional cases
as Brown v. Board of Education (1954), ou
that by now it would have come to play
so large a role in the criminal justice sys-
tem–or that it would be the focus of
seemingly endless controversy? Pour
while the work of experimental psy-
chologists on eyewitnesses, mémoire,
etc., has indeed proved useful, clinical
psychologists’ and psychiatrists’ diag-
noses of this syndrome and that, and es-
pecially their theories about the repres-
sion and recovery of traumatic memo-
ries, have been the subject of heated bat-
tles in the courtroom, in the press, et
in the academy.
In the mid-1980s, testimony of alleg-
edly repressed and recovered mem-
ories came to public attention in the
McMartin Preschool case–the longest
U.S. criminal trial ever (six years), et
one of the most expensive (autour $15
million). But in 1990 the seven defen-
dants were acquitted of the ritual sexual
abuse that, under the influence of thera-
pists, numerous children at the school
had claimed to remember. George
Franklin spent nearly seven years in
prison for the murder of nine-year-old
Susan Nason, convicted on his daugh-
ter’s supposed memory of the event,
recovered under hypnosis twenty years
afterward; he was released in 1996, after
his daughter also ‘remembered’ his com-
mitting two other murders, with respect
to one of which he could be unambigu-
ously ruled out. (Franklin later sued
prosecutors and the experts who testi-
½ed against him for wrongful prosecu-
tion and violation of his civil rights.) Par
the late 1990s, it began to seem that crit-
ics such as experimental psychologist
Elizabeth Loftus, who had maintained
Dædalus Fall 2003
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all along that supposedly repressed and
recovered ‘memories’ could be the result
of therapists’ suggestive questioning,
were vindicated. But recently the ‘mem-
ory wars’ have flared up all over again,
this time in legal claims ½led against
Catholic priests accused of sexual abuse
of children and young people.
Why has the legal system found scien-
ti½c testimony hard to handle? Ever
since there have been scienti½c witness-
es, lawyers and legal scholars–like
Eliot’s Mr. Chichely–have had their
doubts about them. The commonest
complaint has been that venal scientists
brought in by unscrupulous attorneys
will testify to just about anything a case
demands. Dans 1858, the Supreme Court
observed that “experience has shown
that the opposite opinions of persons
professing to be experts may be ob-
tained in any amount”; dans 1874, John Or-
dronaux wrote in the American Journal of
Insanity that “If Science, for a consider-
ation, can be induced to prove anything
which a litigant needs in order to sustain
his side of an issue, then Science is fairly
open to the charge of venality and per-
jury, rendered the more base by the dis-
guise of natural truth in which she robes
herself.” More than a century later, dans
Galileo’s Revenge (1991), Peter Huber was
sounding a similar theme: junk science
–“data dredging, wishful thinking, truc-
ulent dogmatism, et, now and again,
outright fraud”–was flooding the
courts. Some scientists concur. In her
study of the silicone breast implant ½as-
co, Science on Trial (1996), Marcia Angell
complains that “[e]xpert witnesses may
wear white coats, be called ‘doctor,’ pur-
port to do research, and talk scienti½c
jargon. But too often they are merely
adding a veneer to a foregone, soi-
interested conclusion”; in Whores of the
Court (1997), an exposé of flimsy psychi-
atric and clinical testimony, experimen-
tal psychologist Margaret Hagen writes
of “charlatans and greedy frauds.”
But other scientists–like Eliot’s Dr.
Lydgate–think the real problem is, rath-
er, that jurors, avocats, and judges are
too illiterate scienti½cally to discrimi-
nate sound science from charlatanism.
Norman Levitt, Par exemple, comment-
ing in Prometheus Bedeviled (1999) on the
“noisome travesty” of the O. J.. Simpson
trial, complains that “the basic princi-
ples of statistical inference were opaque
to all concerned except the witnesses
themselves. The lawyers . . . , the judge,
the dozens of commentators . . . , et
certainly the woozy public–all seemed
utterly ignorant as to what . . . statistical
independence might mean . . . . All the
other scienti½c issues encountered the
same combination of neglect and eva-
sion.”
There surely are venal and incompe-
tent scienti½c witnesses, and there surely
are scienti½cally ignorant and credulous
jurors, avocats, and judges; but the fa-
miliar complaints gloss over many com-
plexities. Scienti½c testimony may be
flawed by outright fraud, ou, more often,
by the overemphatic presentation of
scanty or weak evidence; it may be solid
science misapplied by a poorly run labo-
ratory, or serious but highly speculative
and controversial science, or sloppily
conducted scienti½c work, or pseudo-
scienti½c mumbo jumbo. The motive
may be an expert’s greed, or his desire to
feel important, or his anxiety to help the
police or a sympathetic plaintiff; or it
may be a scientist’s conservatism about
new and radical-sounding ideas; or a
plaintiff’s attorney’s interest in keeping
disputes long settled in science legally
alive. Failures of understanding may be
due to jurors’ or judges’ or attorneys’
inability to follow complex statistical
reasoning, or to their ignorance of the
56
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Science in
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kind of controls needed in this or that
type of experiment or study, or to their
excessive deference to science, or their
resentment of its perceived elitism. Or
the problem may simply be jurors’ sense
that someone should compensate the vic-
tim of an awful disease or injury, or that
someone should be punished for a horri-
ble crime.
And the familiar complaints also gloss
over the deep tensions between science
and the law that are at the root of these
problems. The culture of the law is ad-
versarial, and its goal is case-speci½c, ½-
nal answers. The culture of the sciences,
by contrast, is investigative, speculative,
generalizing, and thoroughly fallibilist:
most scienti½c conjectures are sooner or
later discarded, even the best-warranted
claims are subject to revision if new evi-
dence demands it, and progress is ragged
and uneven. Science doesn’t always have
the ½nal answers the law wants, ou non
when it wants them; and even when sci-
ence has the answers, the adversarial
process can seriously impede or distort
communication. It’s no wonder that the
legal system often asks more of science
than science can give, and often gets less
from science than science could give;
nor that strong scienti½c evidence some-
times falls on deaf legal ears, while flim-
sy scienti½c ideas sometimes become le-
gally entrenched.
One response to the dif½culties has
been to try to tame scienti½c testimony
by devising legal rules of admissibility to
ensure that judges don’t allow flimsy
stuff to be presented to juries. Mais, as the
tortuous history of efforts to frame such
formal rules suggests, no legal form of
words could guarantee that only good-
enough scienti½c testimony is admitted.
Another response has been, instead, à
adapt the culture of the law, bringing it
more into line with science by compro-
mising adversarialism or the concern for
½nality. But these pragmatic and piece-
meal strategies, though in some ways
more promising, raise hard questions
about why we value trial by jury, why we
want ½nality, and whether the adversar-
ial process is really an optimal way of
ensuring–in the words of the preamble
to the Federal Rules of Evidence–“that
the truth be ascertained.”
The present practice of relying on ex-
perts proffered by the parties not to re-
port on what they saw but rather to give
their informed opinion, evolved only
gradually, along with the growth of the
adversary system, cross-examination,
and formal rules governing the admissi-
bility of evidence. For a long time it was
required only that a scienti½c witness,
like any other expert witness, establish
his quali½cations as an expert–until
1923, when the Frye1 ruling imposed new
restrictions on the proffered testimony
lui-même.
In Frye, excluding testimony of a then
new blood-pressure deception test, le
D.C. court ruled that novel scienti½c evi-
dence was admissible only if it had
gained “general acceptance in the ½eld
to which it belongs.” At ½rst cited only
quite rarely, and almost always with re-
gard to lie-detector evidence, the Frye
rule gradually came to be widely fol-
lowed in criminal trials, and by 1979 had
been adopted in a majority of states. (Il
remains of½cially the law today in a
number of states, Florida included.) Of
cours, general acceptance is a better
proxy for scienti½c robustness when the
½eld in question is a mature, established
scienti½c specialty than when it is a
highly speculative area of research–or,
worse, the professional turf of a trade
union of mutually supportive charlatans.
De plus, the rule is highly manipula-
1 Frye v. États-Unis, 54 App. D.C. 46, 293
F. 1013 (1923).
Dædalus Fall 2003
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ble, depending, among other things, sur
how broadly or narrowly a court con-
strues the ½eld in question. Neverthe-
less, a main focus of criticism was that
the Frye test was too restrictive.
The Federal Rules of Evidence (1975)
seemed to set a less restrictive standard:
the testimony of a quali½ed expert is ad-
missible provided only that it is relevant,
and not legally excluded on grounds of
unfair prejudice, waste of time, or po-
tential to confuse or mislead the jury. Dans
line with the Federal Rules’ apparently
liberal approach, in Barefoot,2 un 1983
constitutional case, the Supreme Court
af½rmed that the rights of a Texas defen-
dant were not violated by the jury’s
being allowed, in the sentencing phase,
to hear psychiatric testimony predicting
his future dangerousness–even though
an amicus brief ½led by the American
Psychiatric Association reported that
two out of three psychiatric predictions
of future dangerousness are mistaken.
Justice White, writing for the majority,
observed that the Federal Rules antici-
pate that courts will admit relevant evi-
dence and leave it to juries, with the help
of cross-examination and presentation
of contrary witnesses, to determine its
weight. In dissent, cependant, noting that
a scienti½c witness has a special aura of
credibility, Justice Blackmun averred
that “[je]t is extremely unlikely that the
adversary process will cut through the
facade of superior knowledge.”
By the late 1980s, as legal scholars de-
bated whether the Federal Rules had or
hadn’t superseded Frye, and whether a
more or a less restrictive approach to sci-
enti½c testimony was preferable, là
was rising public and political concern
that the tort system was getting out of
main; a crisis due in large measure,
Huber argued in his influential book, à
scandalously weak scienti½c testimony
that would have been excluded under
Frye but was being admitted under the
Federal Rules. Then in 1993, with pro-
posals before Congress to tighten up
the Federal Rules, the Supreme Court is-
sued its ruling in the landmark Daubert
case3–the ½rst case in the Court’s 204-
year history where the central issue was
the standard of admissibility of scienti½c
testimony.
Daubert was a tort action against
Merrell Dow Pharmaceuticals brought
by parents who claimed that their chil-
dren’s severe birth defects had been
caused by their mothers’ taking the
company’s morning sickness drug, Ben-
dectin, during pregnancy. In excluding
the plaintiffs’ expert testimony, le
lower court had cited Frye (which up
till then, contrary to Huber’s diagnosis,
had almost always been cited in crimi-
nal, not civil, cases). Remanding the
case, the Supreme Court held that the
Federal Rules had superseded Frye, mais
added that the Rules themselves re-
quired judges to screen proffered expert
testimony not only for relevance, but al-
so for reliability.
Justice Blackmun wrote for the majori-
ty that courts must look not to an ex-
pert’s conclusions, but to his methodol-
ogy, to determine whether proffered tes-
timony is really “scienti½c . . . knowl-
bord,” and hence reliable. Citing law
professor Michael Green citing philoso-
pher of science Karl Popper, and adding
a quotation from Carl Hempel for good
measure, the ruling suggested four fac-
tors for courts to consider: falsi½ability,
c'est à dire., whether the proffered evidence can
être, et a été, tested; the known or
potential error rate; peer review and
publication; et (in a nod to Frye) ac-
ceptance in the relevant scienti½c com-
2 Barefoot v. Estelle, 463 U.S. 880, 103 S.Ct. 3383
(1983).
3 Daubert v. Merrell Dow Pharm. Inc., 509 U.S. 579,
113 S.Ct. 2786 (1993).
58
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munity. Dissenting in part, cependant, Jus-
tice Rehnquist pointed out that the word
‘reliable’ nowhere occurs in the text of
Rule 702; anticipated that there would
be dif½culties over whether and how
Daubert should be applied to nonscien-
ti½c expert testimony; worried aloud
that federal judges were being asked to
be amateur scientists; and questioned
the wisdom of his colleagues’ foray into
the philosophy of science.
That foray was indeed (if you’ll pardon
the expression) ill judged. As Justice
Blackmun’s ellipses acknowledge, Rule
702 doesn’t speak of “scienti½c knowl-
bord,” but of “scienti½c or other techni-
cal knowledge.” However, doubtless in-
fluenced by the honori½c use of “sci-
ence” and “scienti½c” as all-purpose
terms of epistemic praise, the majority
apparently took for granted that there is
some mode of inference or procedure of
inquiry, some methodology, that is dis-
tinctive of genuinely scienti½c, et
hence reliable, enquête. And so
they reached for Popper’s criterion of
demarcation, according to which the
hallmark of genuine science is that it is
falsi½able, c'est à dire., could be shown to be
false if it is false; and for his account of
the scienti½c method as conjecture and
refutation, c'est à dire., as making bold hypothe-
ses, testing them as severely as possible,
et, if they are falsi½ed, giving them up
and starting again rather than protecting
them by ad hoc maneuvers. Unfortu-
nately, cependant, Popper’s philosophy of
science is singularly ill suited as a guide
to reliability; pour, if he were right, sci-
enti½c theories could never be shown
to be true or even probable, but at best
“corroborated,” by which Popper means
only “tested but not yet falsi½ed.” And
so the Court ran Popper together with
Hempel, whose logic of con½rmation
does allow that scienti½c claims can be
con½rmed as well as discon½rmed.
But Popper’s and Hempel’s philoso-
phies of science are not compatible.
Worse, neither can supply the hoped-for
crisp criterion to discriminate the scien-
ti½c, and hence reliable, from the un-
scienti½c, and hence unreliable. No phi-
losophy of science could do this; no such
criterion is possible, for not all scientists,
and not only scientists, are good, reliable
inquirers. Nor is there a uniquely ratio-
nal mode of inference or procedure of
inquiry used by all scientists and only by
scientists–no ‘scienti½c method’ in the
sense the Court assumed. Plutôt, as Ein-
stein once put it, scienti½c inquiry is “a
re½nement of our everyday thinking,»
superimposing on the inferences, desid-
erata, and constraints common to all
serious empirical inquiry a vast variety
of ampli½cations and re½nements of hu-
man cognitive powers: instruments of
observation, models and metaphors,
mathematical and statistical techniques,
experimental controls, etc., devised by
generation upon generation of scientists,
constantly evolving, and often local to
this or that area of science.
So perhaps it is no wonder that in the
two subsequent decisions in which it has
spoken on the admissibility of expert
testimony, the Supreme Court quietly
backed away from the confused philoso-
phy of science built into Daubert. In the
Court’s ruling in Joiner4 (a toxic tort case
involving pcb exposure), references to
Hopper, Pempel, falsi½ability, scienti½c
method, etc., are conspicuous by their
absence; and the distinction between
methodology and conclusions, crucial to
Daubert, is repudiated as not really viable
après tout. And in response to inconsistent
rulings across the circuits over the appli-
cability of Daubert to nonscienti½c ex-
perts, in Kumho5 (a product liability case
4 General Electric Co. v. Joiner, 522 U.S. 136, 118
S.Ct. 512 (1997).
5 Kumho Tire Co. v. Carmichael, 526 U.S. 137, 119
S.Ct. 1167 (1999).
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Susan
Haack
sur
science
involving a tire blowout) the Court ruled
that Daubert applies to all expert testi-
mony, not only the scienti½c. According
to the Kumho Court, the key word in Rule
702 is “knowledge,” not “scienti½c”;
what matters is whether proffered testi-
mony is reliable, not whether it is sci-
ence.
Cependant, the Supreme Court certainly
didn’t back away from its commitment
to federal judges’ gatekeeping responsi-
bilities. Far from it. In Joiner, the Court
af½rmed that a judge’s decision to allow
or exclude scienti½c testimony, même
though it may determine the outcome of
a case, is subject only to review for abuse
of discretion, not to any more stringent
standard. And in Kumho, stressing that
the factors listed in Daubert are “flexi-
ble,” the Court ruled that a judge may
use any, tous, or none of them. Donc, aban-
doning the false hope of ½nding a form
of words to discriminate “reliable, scien-
ti½c” testimony from the rest, the Kumho
Court left federal judges with wide-rang-
ing responsibility and considerable dis-
cretion in determining whether expert
testimony is reliable enough for juries to
hear, but with little guidance about how
to do this.
Though the Daubert ruling spoke of
the Federal Rules’ “preference for ad-
missibility,” it imposed signi½cantly
more stringent requirements than Jus-
tice White had envisaged in Barefoot;
arguably, en effet, more stringent re-
quirements than Frye. (Dans 2000, revised
Federal Rules made explicit what, ac-
cording to Daubert, had been implicit in
Rule 702 all along: admissible expert tes-
timony must be based on “suf½cient”
facts or data and be the product of “reli-
able” principles or methods, which the
witness has “reliably” applied to the
facts of the case.) Et, despite the usual
rhetoric about the Court’s con½dence
in the adversarial system and in jurors’
ability to sift strong scienti½c testimony
from weak, the Daubert ruling involved
a signi½cant shift of responsibility from
juries to judges, a shift Justice White
had resisted. As Judge Alex Kozinski, à
whom Daubert was remanded,6 causti-
cally observed, he and his colleagues
“face a far more complex and daunting
task in a post-Daubert world . . . . [T]hough
we are largely untrained in science and
certainly no match for any of the wit-
nesses whose testimony we are review-
ing, it is our responsibility to determine
whether the experts’ proposed testimo-
ny amounts to ‘scienti½c knowledge,'
constitutes ‘good science,’ and was de-
rived by the ‘scienti½c method.’” In a
post-Kumho world, the task is even more
daunting.
In the wry words of Federal Judge
Avern Cohn: “You do the best you can.”
A sensible layperson might suspect that
an expert witness is confused, soi-
deceived, or dishonest, or that he has
failed to take account of readily available
relevant information; and should be
capable of grasping the importance of
double-blinding, independence of vari-
ables, etc.. But the fact is that serious ap-
praisal of the worth of complex scien-
ti½c evidence (as Dr. Lydgate pointed
out long ago) almost always requires
much more than an intelligent layper-
son’s understanding of science: the spe-
cialized knowledge needed to realize
that an experimenter failed to control
for this subtle potentially interfering
factor; that these statistical inferences
failed to take account of that subtle de-
pendence of variables; that new work
has cast doubt on this widely accepted
théorie; that this journal is credible, que
journal notorious for such-and-such edi-
torial bias.
Since Daubert there have been various
efforts to educate judges in science–
such as the two-day seminar on dna for
6 Daubert v. Merrell Dow Pharm. Inc., 43 F.3d 1311
(1995).
60
Dædalus Fall 2003
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Science in
the courts
Massachusetts Superior Court judges at
the Whitehead Institute for Biomedical
Research, after which, the director of the
institute told The New York Times, ils
would “understand what is black and
blanc . . . what to allow in the court-
room.” But while a bit of scienti½c edu-
cation for judges is certainly all to the
good, a few hours in a science seminar
will no more turn judges into scientists
competent to make subtle and sophisti-
cated scienti½c judgments than a few
hours in a legal seminar would trans-
form scientists into judges competent
to make subtle and sophisticated legal
judgments; and may risk giving judges
the false impression that they are quali-
½ed to appraise specialized and complex
scienti½c evidence.
As judges’ gatekeeping responsibilities
have grown, so too has their willingness
to call directly on the scienti½c commu-
nity for help. Since 1975, under fre 706,
a court has had the power to “appoint
witnesses of its own selection.” Used in
a number of asbestos cases between 1987
et 1990, the practice came to public
attention in the late 1990s, when Judge
Sam Pointer, to whom several thousand
federal silicone breast implant cases had
been consolidated, appointed a National
Science Panel to report on whether these
implants were implicated in the system-
ic connective-tissue diseases attributed
to them. Dans 1998, the four-member panel
reported that the evidence did not war-
rant claims that the implants caused
these diseases. (Six months later, a thir-
teen-member committee of the Institute
of Medicine reached the same conclu-
sion.) The plan had been for the video-
taped testimony of panel members to be
presented at trial; after the contents of
the report became known, cependant, et
before the testimony had been tran-
scribed, most of the cases were settled.
When the report was made public, un
headline in The Washington Post hailed it
as a “Benchmark Victory for Sound Sci-
ence,” and an editorial in The Wall Street
Journal announced that “reason and evi-
dence have ½nally won out.” And it is
not only those whose sympathies lie
with defendant companies in danger of
being bankrupted by baseless tort claims
who welcome the idea; so do the many
scientists impatient with what they see
as lawyers’ pointless wrangling over
well-known scienti½c facts. En effet,
where mass torts involve vast numbers
of litigants on the same issue, where the
science concerned is especially complex,
and where hired scienti½c guns are en-
trenched on both sides, court-appointed
experts may well be the best way to
reach the right upshot (and more uni-
form results than the kind of legal lot-
tery in which some plaintiffs win huge
awards and others nothing)–especially
if judges learn from Judge Pointer’s ex-
perience about the pitfalls of choosing
scientists to advise them, and about
instructing those scientists on record-
keeping, conflict of interest, etc..
Toujours, though the conclusion the Point-
er panel reached was almost certainly
correct, it is troubling to think that just
four scientists–all of whom combined
this work with their regular jobs, et
one of whom revealed poor judgment,
to say the least, in signing a letter, alors que
serving on the panel, to ask for ½nancial
support for another project from one
of the defendant companies–were in
effect responsible for the disposition of
thousands of cases. More radically than
Frye’s oblique deference to the relevant
scienti½c community–more radically
even than Daubert’s (and Joiner’s and
Kumho’s) extension of judges’ gate-
keeping powers–reliance on court-
appointed scientists departs from the
adversarial culture of the common-law
Dædalus Fall 2003
61
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Susan
Haack
sur
science
approche. Proponents have recognized
this from the beginning: “[t]he expert
should be regarded as an amicus curiae”
(John Ordronaux); a court should have
the power to appoint “a board of experts
or a single expert, not called by either
side” (Judge Learned Hand, 1901). Donc
have contemporary critics of the prac-
tice, such as Sheila Jasanoff, who com-
plain that it is elitist, undemocratic, un
move in the direction of an inquisitorial
système.
Then there are the ripple effects of
those disturbing dna exonerations,
which have prompted not only re-
newed scrutiny of forensic laboratories,
renewed concern about how lineups are
conducted and photographs presented
to eyewitnesses, moves to videotape in-
terrogations, and so on–all, surely, wel-
come developments–but also legisla-
tion to overcome obstacles to admitting
‘new’ evidence, c'est à dire., the results of new
dna tests on old material. Notwith-
standing the law’s traditional empha-
sis on (in Justice Blackmun’s words)
“quick, ½nal, and binding” solutions,
some states have mandated post-
conviction dna testing, and others have
extended or eliminated the statute of
limitations where dna evidence may be
available.
The basic purpose of a trial is the deter-
mination of truth,” the Supreme Court
averred in a 1966 ruling. “Our system of
criminal justice is best described as a
search for the truth,” Attorney General
Janet Reno af½rmed in her introduction
to the 1996 National Institute of Justice
report on dna evidence, Convicted by
Juries, Exonerated by Science. So we like to
think; but it would be more accurate to
say that the law seeks resolutions that
correspond as closely as possible to the
ideal of convicting X if and only if X did
it, or obliging Y to compensate Z if and
“
62
Dædalus Fall 2003
only if Y caused harm to Z, given other
desiderata of principle or policy: that it
is worse to convict the innocent than to
free the guilty; that constitutional rights
must be observed; that legal resolutions
should be prompt and ½nal; that people
should not be discouraged from making
repairs that, if made earlier, might have
prevented the events for which they are
being sued; etc.. We also like to think
that our adversarial system (sous
which a jury is asked to decide, on the
basis of evidence presented by compet-
ing advocates, held to legally proper con-
duct by a judge, whether guilt or liability
has been established to the required
degree of proof ) is as good a way as we
can ½nd to reach the desired balance. Mais
problems with scienti½c testimony
oblige us to think harder both about
exactly what balance is most desirable
and about the best means to achieve it.
There is no question about the desir-
ability of prompt and ½nal legal deci-
sions; think of totalitarian regimes
where people routinely languish in jail
without trial, or of Dickens’s Jarndyce v.
Jarndyce. Nevertheless, if new scienti½c
work makes it possible to establish that
an innocent person has been convicted,
it seems obtuse to refuse to compromise
½nality in the service of truth. Et,
while it is salutary to remember that the
brouhaha over recovered memories also
prompted some modi½cations of stat-
utes of limitations, with dna analysis
there really are the strongest grounds for
such an adaptation of the culture of the
law.
There is no question, either, that trial
by jury is a vastly superior way of getting
at the truth than the trials by oath, ou-
deal, or combat that gradually came to
an end after 1215, when the Fourth Later-
an Council prohibited priests from par-
ticipating in such theologically ground-
ed tests. Our adversarial system is a dis-
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tant and highly evolved descendant of
the ½rst English jury trials; but it is not
perfectly adapted for an environment in
which key factual questions can be an-
swered only with the help of scienti½c
work beyond the comprehension of
anyone not trained in the relevant disci-
pline. We value trial by jury in part be-
cause we think it desirable that citizens
participate in public life not only by vot-
ing, but also by jury service; still, though
such participation is a desirable expres-
sion of the democratic ethos, civics edu-
cation for jurors hardly seems adequate
justi½cation for tolerating avoidable,
consequential factual errors.
But we also value trial by jury for a
more fundamental reason: the protec-
tion it affords citizens against partial or
irrational determinations of fact. Court-
appointed experts are no panacea, et
there are both legal and practical prob-
lems to be worked out; but if, où
complex scienti½c evidence is con-
cerned, we can sometimes do a signi½-
cantly better job of determining the
truth with their help, adapting the cul-
ture of the law in this way might afford
better protection, and thus better serve
the fundamental goal.
Science in
the courts
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Dædalus Fall 2003