Filipe Santos
Abstract:
The use of DNA
technologies for criminal investigation purposes illuminates an
interplay of knowledge and expertise wheremeaning and relevance
of biological traces are negotiated. Through the analysis of
five criminal cases that took place in Portugal between 1995
and 2010, and where DNA technologies were used, this article will
focus on the dialogues established between the police and the
forensic laboratories. I will argue that, on the one hand, the
police investigators uses of DNA technologies seek to legitimate and
provide an external source of neutrality and objectivity to the
constructed narratives surrounding the commission of a crime.
On the other hand,
laboratories and forensic experts engage in the
delimitation and preservation of their professional autonomy
by developing boundary work around their scientific expertise
through the translation and conversion of criminal traces into
scientific artifacts.
L'utilisation des technologies ADN à des fins d'enquête criminelle
éclaire une interaction de connaissances et d'expertise où la
signification et la pertinence des traces biologiques font l'objet
d'une négociation. A travers l'analyse de cinq affaires pénales qui
ont eu lieu au Portugal entre 1995 et 2010, et où les technologies
ADN ont été utilisées, cet article se concentrera sur les
dialogues établis entre la police et
les laboratoires forensiques. Mon argument est que, d'une part, les
usages faits par les enquêteurs des technologies de ADN cherchent à
légitimer et à fournir une source extérieure de neutralité et
d’objectivité à des récits construits autour de la commission
d'un crime. D'autre part, les laboratoires et les experts forensiques
se livrent à la délimitation et à la préservation de leur
autonomie professionelle en développant un travail de traçage de
limites autour de leur expertise scientifique à travers la
traduction et la conversion de traces criminelles en artefacts
scientifiques.
New Genetics and Society,
Volume 33, Issue 2, pp. 181-203
Introduction
This
article draws from the analysis of five case studies of criminal
cases that occurred in Portugal between 1997 and 2007. The wider aim
of my investigation is to analyze the modes of the heterogeneous
constructivism (Hess 1997) of DNA technologies in judicial contexts
by focusing on the activities and discourses of the police,
magistrates, forensic experts, lawyers, and also the journalistic
coverage of the cases.
The
purpose of this paper focuses a particular element of the social
construction regarding the forensic use of DNA technologies, namely
the dialogues established between the police investigators and the
forensic laboratories, rendering specificand situated forms of
knowledge and expertise that illustrate the socially constructed
dimensions of the forensic uses of DNA technologies (Cole and Lynch
2006; Cole 2012). A first section of this paper will provide a
synthesis of the sample of criminal cases on which this analysis is
grounded.
The
second section will draw on examples from each case in order to
conceptualize the general stances of the actors and their
institutions. I will argue that, on the one hand, the police
investigators’ discourse reveals what I have called “evidentiary
pragmatism” while, on the other hand, reports from the forensic
experts can be characterized by its “epistemic distancing”.
The
Portuguese criminal justice system is, like many other continental
justice systems, oriented by an inquisitorial principle. A common
feature is that the “search for the truth”, constitutes the
ultimate objective of any criminal investigation and judicial
proceeding. When a crime is detected, it is reported to the competent
entity, which is the prosecution service (Ministério Público–MP),
that will coordinate the inquiry with the assistance of the criminal
police agencies. These agencies (Polícia Judiciária – PJ;
Polícia de Segurança Pública–PSP
and the Guarda Nacional Republicana–GNR)
may perform the necessary actions and diligences for the development
of the investigation, under the supervision of the judiciary
authority. The most serious and/or complex crimes (defined by Law
48/2008) fall under the exclusive competence of the Polícia
Judiciária (PJ).
In
an inquisitorial justice system, the police, the prosecution, the
judges, and also the laboratories, are all regarded as fully
impartial (Kruse 2012). In this judicial edifice, trial judges are
legally considered to be the ultimate expert in evaluating and
interpreting the evidence brought before the court. Nevertheless, as
stated in article 163 of the Portuguese Code of Criminal Procedure
(2007), technical, scientific or artistic evidence are not the
subject of free interpretation by the trial judge. That is, if for
some reason, the judge does not agree with the expert(s), he or she
must be prepared to fundament their disagreement. The court can
always demand further clarification regarding forensic exams, andthe
defense can submit requests to the judge for new forensic exams or
enroll a forensic expert as witness.
In
summary, the police performs the investigation of a crime under the
supervision of the
Ministério
Público (MP), gathering evidence with the assistance of their own
laboratory (LPC –Laboratory
of Scientific Police) or the State owned laboratory (INMLCF National
Institute of Legal Medicine and Forensic Science). When the police
concludes the inquiry, the MP has to evaluate the facts, classify the
type of crime(s) and, if the inquiry has led to the identification of
suspects, if there is enough evidence to produce an accusation.
When
forensic evidence reaches the courtroom, it is the result of a long
chain of events and decisions, and several formal and informal
exchanges of information between the police investigators and the
laboratory technicians.
During
the inquiry, criminal case files are punctuated by reports of the
officers on the field, either to the investigation coordinator or to
the MP prosecutor. These reports are most informative regarding the
ways in which the criminal narrative is developed, containing the
known “facts” and the speculative outlines of “what happened”,
and what
is
missing from the story. I will use the expression “criminal
narrative” in the same manner that Jasanoff (2006) or Kruse (2012)
refer to the use of familiar cultural and professional story
templates in order to “make sense” of the actors and their
actions, and
also
to interpret the evidence.
This
is similar to the way Dahl (2007) uses the metaphor of the “jigsaw
puzzle” to illustrate the development of a criminal case and the
role of DNA in the courtroom, but also to describe the process of
construction of DNA evidence. Its construction involves several, as
Dahl adequately calls them, “construction workers” in a
production line that begins with the offender and will end with the
judge and members of the jury. This process of construction is
determinant, because: All of these ‘construction workers’ may
influence how the piece of jigsaw puzzle consisting of DNA evidence
is shaped, presented and perceived in a trial. Despite this, DNA is
often presented and perceived as an objective truth; a piece of
jigsaw puzzle that has only one given size, shape and form (Dahl
2007, 222).
The
term “criminal narrative” also conveys the provisional and
frequently inductive character, which is inherent to the unfolding
development of a criminal investigation. A crime scene constitutes a
sensitive and precarious object, which became even more so because of
the possibilities surrounding the collection of biological traces.
The initial approach to a crime scene is often fundamental for its
resolution because it sets in motion a stream of decisions that have
to be made with little or no background information. For example,
what are the physical boundaries of the crime scene, and how many
men, and what sort of equipment should be brought to the crime scene?
The
first impressions and significances attributed to the initial data is
very likely to influence the development of the investigation, which
sometimes changes dramatically in face of new evidence. Williams and
Johnson (2007,371) refer to a “central
impulse” that leads the case investigators to reconstruct a crime’s
sequence of events by studying signs of activity and movement in the
crime scene, and also by applying their professional repertoires
about typified criminal behavior. Often, the initial decisions are
made by the first officer(s) to arrive on the scene of the crime and
the early definition of the situation will help establish a context
under which the circumstances, suspects, and traces will be
discriminated. Hence, as Kruse argues, pre-trial investigations are
also drawn around well
-known
cultural scripts and categories that will play an important role in
ascribinmeaning to forensic evidence (Kruse 2012).
While
there are several approaches by the social sciences to the uses of
DNA profiling and databasing technologies, or its uses and
significance during trials,1especially
in adversarial judicial contexts, its social aspects of the pre-trial
investigation in inquisitorial systems arestill somewhat peripheral.
I will argue that, in analyzing the pre-trial construction of
forensic evidence, it is necessary to consider the dialogues
established between the police and the laboratories.
Note : See, for example, Social Studies of
Science -Special Issue: Contested Identities, 28 (5-6); and also
(Lazer 2004; Lynch et al. 2008; Krimsky and Simoncelli 2011;
McCartney 2006; Aronson 2007; Machado and Prainsack 2012), and
recently the Special Issue of New Genetics and Society –Risky
profiles: societal dimensions of forensic uses of DNA profiling
technologies(Heinemann, Lemke, and
Prainsack 2012).
Methods
The
criteria for the selection of the criminal cases were that DNA
technologies were used in the investigation, that the case files were
available to the public –which meant that a sentence had been
passed or a decision to end proceedings was reached –, and also
that during the investigation and trial the cases received
significant and national media coverage
–which
is relevant in order to analyze the media’s discourses about DNA
technologies, which constitutes another dimension of my wider
research. A time interval for selection was established from 1995,
which corresponds to the early uses of DNA technologies for criminal
investigation purposes in Portugal, and 2010, in order to fulfill the
criteria regarding closed cases. During 2012, I visited the courts
where the case files were archived and was granted access to them.
Each case file was composed of multiple volumes that contained nearly
every detail regarding the investigation, as well as the trials and
subsequent appeals in almost every case. Drawing from a grounded
theory approach (Glaser and Strauss 1967), and since the number of
pages in each case file reached the thousands, I performed an initial
selection of the materials that would constitute the corpus of
analysis that are either related to each case’s progress or,
mainly, to the uses of forensic science and DNA technology. Hence,
the gathered materials are mainly composed by witness and suspect’s
testimonies, police reports, forensic reports, official
communications between judicial entities, sentences and higher court
appeals. I did not collect materials that had no relevant information
for the intended purposes, like bulky phone records, bank
statements,and common service orders.The next section will provide a
briefoverview of the context and development of each case.
Five
criminal cases
This
section aims to provide the reader with a summary description of each
selected case. I will refer to them using the terms and titles that
were adopted by the newspapers. However, when citing from the case
files I will use the case judicial reference and numbering.
(…)
The
“Madeleine McCann” case
In
2007, a couple of British citizens (Kate and Gerry McCann) were on
vacation
in
the Algarve in a resort in Praia da Luz with their three
children (Madeleine 3, Sean and Amelie 2-year-old twins). On
May 3, around 10pm Madeleine was said to have “been taken”
from the room where the children were sleeping. The initial
investigations by the Portuguese police and its crime scene
technicians were not able to find traces of Madeleine or a
perpetrator.
In
late July 2007, a British police specialist suggested that
their two trained cadaver and blood dogs could be used to search a
suspect’s house and several vehicles, as well as the surroundings
of the holiday apartment. All searches were
negative
regarding the only suspect–Robert Murat. However, the dogs
signaled for blood and human decomposition odors in the McCanns’
holiday apartment as well as in their rented car. A forensic team
recovered all materials that were likely to have any
biological stains and sent them to
the
Forensic Science Service in Birmingham, UK.
The
Portuguese laboratories also received some remaining materials for
future analysis (pieces of a curtain and plastic trim from the
McCanns’s rented car). Anbinformal communication between the
laboratory and a liaison officer
regarding
the preliminary results of the DNA exams on the traces
recovered at the apartment and in the car was made available to the
Portuguese police (PJ) and, on 6 and 7 September 2007, Kate and
Gerald McCann were confronted with numerous questions and with a
viewing of the video made of the search dogs marking the scent of
blood and cadaver in the apartment and in the car to which both
offered no explanation. They were both made arguidos for suspicion
of their involvement in their daughter’s disappearance.
However,
the forensic exams did not produce relevant evidence of
Madeleine’s death. On 21 July 2008, the inquiry on the case
was finally closed by the Ministério Público owing to lack of
evidence of any crime being committed by the three arguidos in the
case. Drawing examples from the files of the cases described
above, the following section will explore the character and
conceptualization of the social-legal network by focusing on the
dialogues
between the police investigators and the forensic laboratories.
Results
The
Portuguese forensic context is marked by the
predominance of two institutions (LPC and INMLCF) which have
exclusivity in the provision of forensic
services.
While the LPC is a department of the Polícia Judiciária,
the INMLCF is a state-owned
laboratory of legal medicine that performs forensic
examinations for the public
and private sectors.This is in contrast with the situation in the
United Kingdom where the
provision of forensic services operates in an open market. Lawless
and Williams (2010) have
written about how the privatization of forensic services have shaped
new approaches to the interpretation of evidence, namely through the
formulation of the Case Assessment and Interpretation (CAI)
method. CAI, or the application of bayesian framework of
reasoning to criminal case evidence, employs systematic questioning
of hypothetical prosecution and defense propositions, generating
likelihood ratios in order to assist investigative
decision-making. The questions are structured in hierarchical
levels that take into account the case’s circumstances and assist
in the interpretation of the evidence (source, activity, and
offence).
Ultimately,
as Lawless and Williams suggest, “CAI promotes a form of
forensic science which renders the criminal investigative process
as a form of scientific inquiry itself” (Lawless and Williams
2010,744).
When
observing the Portuguese context, and considering that the
studied cases span a period of ten years (1997-2007), it
appears that the strategic use of forensic science in
criminal investigations is set in a framework of divergent
institutional goals between scientists and the police that,
particularly in the older cases, can hinder a more efficient and
economical use of forensic science.
The
following sections will attempt to describe, by using
examples drawn from the studied criminal cases, two concepts that
can help understand the epistemic tensions that stem from the use of
DNA technologies for criminal investigations.
Epistemic
distancing
The
role that forensic scientists play in criminal investigations
in the Portuguese context is interesting in the sense that, as
Amorim has stated (2012a, 266), there is an
overlap
of two roles: one of criminal investigation, and another of
expert witness.
Amorim
cogently observes that in judicial settings where the same
expert or institution that assists the investigation
(analyzing crime scene samples and/or identifying a
suspect) also acts as expert witness, there is an obvious
source of conflict (2012a,
268).
I argue that this potentially contentious “double role” or role
strain tends to be
avoided
through the laboratory’s “boundary work” (Gieryn 1999),
which translates in this context to the concept of “epistemic
distancing”.
As
the examples drawn from the criminal cases will illustrate,
“epistemic distancing” operates through the prevalence of
scientific discourse, methods,and logic in face of the
cognitive pressures from the judicial system, in order to
preserve institutional and scientific credibility. The
“distancing” can hinder a more efficientuse of forensic
technologies in criminal investigations, since it can alienate
forensic scientists from the objectives of forensic inquiry.
This
concept of “epistemic distancing” is intimately related to
the concept of “evidentiary pragmatism” which attempts to
describe the institutional position of the police towards the
contribution of forensic science for the development of the criminal
investigation. The laboratories’ epistemic distancing appears
configured in three in
interconnected
dimensions : purification, classification and interpretative
limitation. In
the
reports that are produced and provided to the criminal investigators
there is a sense that laboratories actively engage in the protection
of their scientific autonomy and in the
maintenance
of professional standards. In this sense, the dimension of
purification illustrates the manner in which the “impure”
materials are received and thus transformed into scientific objects
of analysis. This transition operates by exhaustive description and
classification, covering the biological or physical traces and also
the packaging made by the agents on the field.
This
is mainly done in order to document the chain of custody, but it also
carries a symbolic effect which demarcates the police work done on
the field from the scientific work of the laboratory.
(...)
The
Madeleine McCann case is probably the most widely publicized criminal
case to date, and it had multiple characteristics that contributed to
its long media exposure (Machado and Santos 2009,150). In the
analysis of this case, the laboratories’ “epistemic distancing”
was not as evident as in the previous cases. Although, for example,
in the “Serial Killer of Santa Comba Dão” case, there is
extensive and thorough documentation of the chain of custody, the
three dimensions can be found in the forensic reports. The Portuguese
forensic reports from the INMLCF on the Madeleine McCann case have a
slightly different approach, since the materials received are not
thoroughly described as in earlier cases. This could possibly be
attributed to the fact that the materials were collected and sent by
the LPC and not from inspectors at the crime scene. Furthermore,
there was an extraordinary number of traces that were collected and
sent for analysis (hairs, fibers, and samples). In addition, the main
report is
signed by the directors of all three main national delegations of the
INMLCF.
The
characteristics of this case make it stand apart from the other
selected cases, insofar that it employed the most resources by far
and, furthermore, because it involved international cooperation with
multiple police forces. The close cooperation with the British police
resulted in two very important steps in the investigation: the use of
EVRD and CSI dogs and
the commission of the forensic DNA exams to the Forensic Science
Service. The dog’s handler and trainer asserted, however, that
although the dogs demonstrate through their training capabilities
beyond any known forensic equipment or technique, any alert for blood
or cadaver odor must always be confirmed in a forensic laboratory.
Il a dit aussi que son chien n'avait jamais marqué en vain, autrement dit ne s'était jamais trompé ! Although the EVRD and CSI dogs were brought to the Algarve to help in
searches to the house and garden of the only suspect – Robert Murat
–, the police decided to perform a search in the Ocean Club
apartments and a total of ten vehicles.
Il est complètement faux que les chiens britanniques soient venus dans le but de participer aux recherches dans la maison et le jardin de Robert M. Les recherches K9 ont été planifiées par Mark Harrison, le spécialiste des personnes disprues, et c'est lui qui a décidé d'amener les chiens dans l'appartement 5A. Il est du reste logique de procéder de cette manière, autrement dit à partir de l'endroit où la personne disparue a été vue pour la dernière fois.
At this point, the results of
the canine inspection are publicly known, as they were widely
reported in the media.
In
order to withdraw from eventual misinterpretations, the dogs’
handler filed a report where he described the dogs’ reactions and
their interpretation. Nevertheless, the summary of the report closes
by stating that : My professional opinion as regards to the EVRD’s
alert indications is that it is suggestive that this is “cadaver
scent” contaminant. This does not how however suggest a motive or
suspect as cross contamination could be as a result of a number of
given scenarios and in any event no evidential or intelligence
reliability can be made from these alerts unless they can be
confirmed with corroborating evidence (201/07.0GALGS, p. 2477).
C'est erroné, Martin Grime, car il a un nom !, ne conclut pas son rapport de cette façon, il ne s'agit ici que de la conclusion du pararaphe concernant les recherches K9 dans le garage.
EVRD
–Enhanced Victim Recovery Dog; CSI–Crime Scene Investigation
(Human blood search dog)
On
4 September, the Portuguese police had access to an informal
communication between the laboratory and a liaison officer of the
Leicester police. The content was far from categorical and merely
suggested, rhetorically, that while some components of the Low Copy
Number profile from a dry swab collected from a tile behind the sofa
in apartment G5A that was rented by the McCanns, it rendered a mixed
profile that made any interpretation too complex: What we need to
consider, as scientists, is whether the match is genuine and
legitimate (...)
The
individual components in Madeleine’s profile are not unique to her;
it is the specific combination of 19 components that makes her
profile unique above all others. Elements of
Madeleine’s
profile are also present within the profiles of many of the
scientists here (...)It’s
important to stress that 50% of Madeleine’s profile will be shared
with each parent (...)
Therefore,
we cannot answer the question: Is the match genuine or is it a chance
match? (...) What questions will we never be able to answer with LCN DNA
profiling? When wasthe
DNA deposited? How was the DNA deposited? What body fluid(s) does the
DNA originate from? Was a crime committed ? (201/07.0GALGS, p. 2618).
The
nature of this informal communication can also be interpreted as a
form of “epistemic distancing”insofar as it emphasizes the
boundaries and limits of DNA technology concerning the answer to
questions that pertain and are only relevant to the criminal
investigation.
Thus,
the expression “as scientists” marks a distinction between an
empirically verified probability of a fact from mere assumption.
This
email is also significant because it exposes the differences between
a CAI (Case Assessment and Interpretation) paradigm of incorporating
forensic evidence into criminal investigations–considering
questions from both the prosecution and the defense –from the
Portuguese “inquisitorial paradigm”, where forensic evidence is
sought in order to support the criminal narrative. Acting on this
premise, the Portuguese police used the information on the email (a
partial match) to confront the McCanns with the existence of
Madeleine’s DNA on places that were signaled by the EVRD and CSI
dogs.
The
next section will approach the police’s “evidentiary pragmatism”,
which tends to operate on a somewhat contrasting logic from that of
the “epistemic distancing”. The institutional functions,
concerns, and expectations of the police shape their instrumental use
of forensic DNA technologies for criminal investigation purposes.
Hence, the police’s interpretation of the probative value of DNA
should not be separated from their particular interpretation in the
context of each criminal case –and this is a central feature of the
dialogue between the police and the laboratories, insofar as the
police turns to the laboratories’ reports for answers that are
systematically constructed in a way that transfers the burden of
interpretation to the police.
Evidentiary
pragmatism
The
first dimension and perhaps the main use of DNA technologies by the
police is “identification”, that is, to gather as manybiological
stains as possible, in order to be able to produce working hypothesis
about what happened. The initial approachto what has been established
as the crime scene is often fundamental for the resolution of the
investigation, since it sets in motion a process of discrimination of
the traces, individuals, and the relevant information, in frequently
chaotic sceneries, where the first impressions and interpretations
can influence the course of the investigation. Williams and Johnson
(2007,363)refer to a “central impulse” which leads criminal
investigators to “reconstruct” the sequenceof events that led to
the crime. This is performed through professional repertoires of
interpretation of the observable signs of movement and activity
through the understanding of typified criminal behavior and the
general knowledge about each type of crime. However, the early
attempts of reconstruction are necessarily rough sketches, made in
order toreduce the complexity of a crime scene and focus the
investigation on acquiring further details.It is evident from the
analyzed cases that early definitions and interpretations are
determinant of the type of inspections and forensic procedures to be
adopted.
(…)
As
the criminal situation starts to become defined, forensic science is
used by the investigation in order to, as Kruse states,
materialize “the (criminal) body at the same time
as it establishes the connection between a particular body
and a particular crime scene” (Kruse 2010, 2). In
this sense, the investigation’s primary concern is to
“identify” bodies and biological traces.
This
is a prominent element in most requests that accompany
biological materials sent to the forensic laboratories.
However, particularly in the earlier cases that were selected,
and whenever there were no presumable suspects, the laboratories
were asked to “perform the adequate exams in order to identify
the DNAof eventual suspects” (704/99.9 JAAVR, p. 40). This
illustrates the distinct approach to forensic science by the
police and the laboratories.Forensic science, and particularly
forensic genetics, does not provide “identification”.
Forensic
genetics can only express probabilities of finding a similar
case, and even a high likelihood ratio does not mean that there are
individual distinctive features in a genetic profile (Amorim
2012a). One could say that the police’s requests for
identification are drawn upon the knowledge and practice of
traditional forensic sciences that relied on untested claims of the
discernible uniqueness (Saks and Koehler 2005). The abstract
notion that it is possible to trace a mark to a unique
source can be useful for criminal investigators in order to draw
strong conclusions in a case (Saks
and Koehler 2008). Thus, the dimension of “identification”
relates to a pragmatic view, insofar as the investigators are not
required to ponder the universality of scientific claims, and it
is notthe police’s concern if a certain profile cannot be
identified to the exclusion of all others in the world–only if it
will include or exclude a suspect. As the investigations
developand there aresome insights into the network of
individuals could have been, legitimately or illegitimately, present
at the crime scene, it is possible to provide the
laboratories with individual samples for comparison.
Identification of the nature and origin of the
biological traces is paramount in establishingthe criminal
narrative, insofar as, for example, blood stains are usually
interpreted as a sign of a violent crime. Nevertheless, it
is important to emphasize that the interpretation and
significance of the stains is framed by the context of the ongoing
criminal narrative.
The
first dimension of “evidentiary pragmatism” is thus
connected with the second: causality. This dimension attempts
to describe the interpretative process that generally follows the
discovery of biological traces, although it can also precede
it. What is relevant is that the narrative hypothesis
matches the stains at the crime scene and vice-versa. For
example, it was after the EVRD and CSI dogs alerted to cadaver and
blood scent in the McCanns’ holiday apartment that the
hypothesis that Madeleine could have died there took shape.
(…)
The
concept of “evidentiary pragmatism” comes to illustrate a
mode of professional reasoning and attainment of
institutional purposes that constitutes a dialogical framework
towards forensic technology and expertise. In other words, the
criminal investigation personnel relates to forensic experts as far
as they expect answers to investigative questions that will
confirm or conform to the developing criminal narrative. As
seen in the above examples (particularly in the Tó Jó and Joana
cases), the police’s “pragmatism” towards forensic evidence
is often biased against a suspect or defendant, insofar as
the institutional pressure to solve a case and obtain a
conviction can lead to exaggerated inferences.
Another
important aspect that emerges from the analysis of the case files is
what could be termed as an “authoritative chain of facts” that
is embedded in the criminal narrative. That is, as the phases
of the criminal procedure advance (inquiry, formal accusation,
trial and sentencing), there are some facts that become
established and are accepted by the succession of legal
actors. This is made evident in the composition of the
several documents that tell the story of “what happened”
and that often have sections that are copy/paste from previous
reports.
Conclusion
From
the analysis of the judicial case files, and particularly the
requests for forensic exams, it can be seen that the
dialogs between police agents and the laboratories
constitute a field of negotiation where organizational
objectives and interests are played out. The role of criminal
investigators in this negotiation can be
characterized
by what I propose to be “evidentiary pragmatism”. The
idea is that criminal investigators ascribe particular and
situated interpretations of the traces found at crime
scenes,which are rendered, explicitly or implicitly, in the
requests that are attached to the traces sent to the laboratories.
Necessarily, these requests make sense in the
pursuit of a storyline that is being hypothesized as the
investigation progresses and a criminal narrative takes shape.
Evidentiary pragmatism is thus a manner of establishing a dialogue
whereby the formulation of forensic requests discursively
implicates the laboratory in the investigative process by stating,
more or less explicitly, what would be the
“desirable” outcomes of the forensic analyses.
Consequently,
the evidentiary pragmatism is a form of interpretative
flexibility of the outputs generated by forensic laboratories
through which task oriented imperatives are performed and achieved.
The
case files themselves are a somewhat “purified” version of the
process of criminal investigation, insofar as the full details
and order of events are not always comprehensible.
These
are also inscribed with forensic reports provided to the criminal
investigation police and to the cases’ prosecutors and
investigating judges. Every trace, crime scene stain, suspect
sample, or object that is received by the laboratory is
subjected to a process of description, categorization, and
translation, in order to isolate the materials from all kinds of
contaminants, both physical and cognitive. This processhas been aptly
described in Susana Costa’s ethnographic work in a Portuguese
forensic laboratory (Costa 2003).This cognitive-instrumental
membrane that separates the laboratoryfrom the outside world is
important in a socio-legal context where the investigating
police, the courts, and the official forensic laboratories are
branches of the criminal justice system under the Ministry of
Justice. Hence, what I have called the “epistemic
distancing” of the forensic laboratories configures a
professional ethos marked by distinctions and differentiations from
the language, practices, classifications, hypothesis and opinions
of the police.
Through
purification, classification, and interpretative limitation,
impure traces, stains and objects collected at crime scenes are
scientifically translated in order to deliver “black boxed”
results which conform to the organizational needs of the police and
the criminal justice system.While the Portuguese criminal
justice system could be characterized by a symbolic
submission of law to science(Santos 2000), since expert
evidence is not a matter to be freely assessedby the judge, during
an investigation that submission is not absolute. Namely,becauseit is
not the trial judge or jury who is to interpret the expert evidence,
but the police investigators, prosecutors and investigating
judges who will make sense of the laboratory results and
inscribe them on the ongoing criminal narrative.Therefore, the
process of investigating a crime allows interpretative flexibility
along a forensic evidentiary chain until a case reaches
trial. At this point, as Helena Machado argues, DNA technologies
are perceived as transcendent of the contingencies of human action,
and as a symbol of neutrality and truth (Machado 2012,280).
Thus, the authoritative status of DNA technologies is seldom
successfully challenged in court, as the complexities and
uncertainties surrounding DNA evidence appear “black-boxed” and
significantly framed in a criminal narrative that a defense lawyer is
rarely prepared to successfully open (Dahl 2007,234).
