There is a “scary
tendency””for
forensic scientists to be
influenced by extraneous
information..., a bias
toward confirming the
hunches of other
investigators on the
case.
Advisory Committee, which aims “to coordinate and support work
at Arizona’s eight crime labs.” The FSAC’s chair is former Superior
Court Judge Ron Reinstein, now a judicial consultant for the
Arizona Supreme Court.
Reinstein is pleased that Arizona has seen none of the allegations
of fraud that other jurisdictions have, or issues of contamination.
One reason for that may be grant requirements, he says. The
Arizona Criminal Justice Commission is able to obtain federal
grants for local labs, grants that require heavy scrutiny.
And Arizona has “good training and leadership” in its eight labs,
all of which are accredited by ASCLD-LAB—the American Society
of Crime Laboratory Directors-Laboratory Accreditation Board.
But in forensic evidence generally, Reinstein says, the word
“match” is in for some much-deserved scrutiny.
“I think people accepted it for so many years, like in ABO blood
typing and hair analysis, people never thought that there was any-
thing beyond the expert saying that there was a ‘match.’ There was-
n’t a whole lot of criticism about it.”
“But as people looked more and more into the forensic area,
they found that a lot of the statements made in court were proba-
bly overstated.”
Reinstein does not think the system nationwide is in crisis,
though he says improvements can be made. The goal, he says, is to
get closer to where we are with DNA, “which is pretty solid, as far
as the science goes; the problem is [sometimes] the people,
whether the evidence is contaminated or not. That’s not necessarily true of all areas,” where the underlying science may be unreliable. He mentions bite-mark and FBI lead-bullet analysis.
Carrie Sperling is executive director of the Arizona Justice
Project, which provides legal assistance to Arizona inmates “with
claims of actual innocence or manifest injustice.” She agrees that
DNA analysis has set a high standard, but she is concerned about
opinion masquerading as science in courtrooms.
Speaking before release of the NAS report, Sperling says she
hopes it will include recommendations that make more clear the
standards that judges apply in admitting and weighing such testimony. And she mentions “oversight,” a term generally disliked by
crime lab scientists.
“My dream come true would be that [the NAS report] recommend independent crime labs that aren’t run by the state or the
local law enforcement. But politically, I don’t know how you get
there, because it’s so entrenched. We’d have to completely revamp
crime labs.”
“Short of that, true independent oversight would be the next
best scenario, so when a sample is handed over to the lab, the sci-
entists themselves don’t know who the suspect is.”
Sperling says there have been instances around the country
where the detective writes a note saying that they need the lab to
match this sample to this person. She says that people in crime labs
see themselves as objective scientists, but empirical studies have
shown that there is no way humans can overcome certain biases.
Not everyone agrees on restricting information given to lab scientists. Susan Narveson, formerly head of the Phoenix Police
Department lab, and now with Strand Analytical Laboratories, an
independent Indiana lab, cautions against comparing lab work
with, say, photo lineups, where extraneous information is clearly
inappropriate.
“From the scientific perspective,” Narveson wrote in response
to questions, “a minimum amount of information on the case synopsis is necessary in order to facilitate the evidence examination and
ensure that it is examined in a thorough, expeditious and appropriate manner.”
Dissenting from that view is Michael Saks, an ASU law professor. He says there is a “scary tendency” for forensic scientists to be
influenced by extraneous information. There is a high risk of “
context effects,” he says, that create a bias toward confirming the
hunches of other investigators on the case. As he wrote in his comments to the NAS committee:
Unfortunately, forensic scientists often claim a disciplinary
exceptionalism: that they are not subject to the same phenomena that have been found in other fields. … Despite the fact that
[context] effects were found in every other field in which they
were tested, forensic scientists insisted that they alone could prevent such effects merely by willing themselves to do so (and
therefore did not need the methodological protections so many
other sciences have adopted).
Narveson and Reinstein agree, though, that undue influence
must be avoided. Lab scientists, says Narveson, “do not welcome
undue pressure or unnecessary interaction with law enforcement or
representatives of the legal system during the examination and
analysis of case evidence.”
The NAS Report
As we went to press, the report finally emerged from the National
Academy on February 18. (Originally due out summer 2008, it was
promised in January, and then late February.) At 255 pages, it contains 13 major recommendations. All are advisory, though it is likely that some federal grants to laboratories will stipulate adherence.
A few of the key recommendations:
• Establish an independent federal entity to set and
enforce best practices in labs, and to fund research
into the scientific bases of forensic methods.
• Remove public forensic labs and facilities from the
administrative control of law enforcement agencies
