Science and the US criminal justice system
There has been a landslide of problems exposed in the criminal justice system that stem from
faulty science being used to convict the innocent.
There are too many examples to dismiss them
as exceptions, or as technical problems that apply only to specific methods.
Instead, there are
basic, fundamental problems in the way that scientific data are being gathered, used, and
presented in our courts.
It is a crisis.
It means that you can live a righteous life, abiding by the
law, and yet become a victim of a faulty prosecution.
It also means that the real criminals are
going free, to commit more crimes and spread the word that they can get away with it.
On paper, the foundation of the US criminal justice system appears to be a triumph for the
Concepts such as “innocent until proven guilty,”
“a jury of peers,” and “the right to
hear accusers” are safeguards to protect us, with the roots of these concepts stemming from the
very inception of this country.
Those of us who have never had a brush with the criminal court
system can be lulled into a sense that it is functioning well.
Sure, we all know that money can be
important in getting a good defense, but the premise is that the innocent are rarely faced with
having to defend themselves (an ironic reversal of our supposed “innocent until proven guilty”
Yet, for those of us with that perception, there has been a shocking embarrassment of
wrongful convictions and of abuses and misuses of science that have come to light recently.
the last 10 years,
1) Over 170 people in US prisons have been released after new evidence showed that they could
not have committed the crime (more than 80 of these were from death row, of the approximately
6,000 people sent to death row since 1976).
The most common cause of mis-conviction was
mistaken identification by eyewitnesses.
2) Hair-matching methods, often used in court to establish that a single hair came from a
particular person, have been declared nonsense.
In 2003, Canada not only abandoned use of
(non-DNA) hair matching methods, but began reviewing convictions that used hair matching, to
see if the convictions should be overturned.
Fingerprints fell from grace.
Long considered the icon of personal identification, fingerprint
experts were finally subjected to proficiency tests in the mid-late 1990s and found to make false
matches 10%-20% of the time.
4) Polygraph tests, widely used by the government though no longer allowed in many courts,
were declared nonsense by a panel of the National Research Council
5) In a flurry of public attention in 2003, the Houston Crime lab lost its accreditation for DNA
typing because of sloppy procedure
The list goes on, but these are some of the major ones. We owe many of these new revelations to
DNA typing, because DNA typing
exposed many of the mis-convictions, and also because it set