
DNA in the dock: flawed techniques send innocent people to prison - kawera
https://www.theguardian.com/science/2017/oct/02/dna-in-the-dock-how-flawed-techniques-send-innocent-people-to-prison
======
avs733
This seems like an ongoing problem with science and the criminal justice
system, especially in the US. Science, and the trustworthiness of science,
become an object of adversarial argument by non experts that have directly
opposing interest, and which often face large disparities in resources with
which to make that argument.

I had a discussion years ago at a conference with an EFF member that they
really ought to (obviously easy for me to suggest) hold training sessions for
judges on the basics of how technology and the internet works. Otherwise, the
courts seem enormously susceptible to bad analogies ('an I.P address is just
like a physical mailing address') that are used in place of actual evidence.

------
dsfyu404ed
The DA has an incentive to convict people. All the people who supply the
evidence have incentives to help out. Who gets convicted isn't all that
important as long as there's a pretty good correlation between a crime being
convicted and someone being punished. Doing "my PHD is dependent on this and
I'm not going to f-it up" work is time consuming and expensive. Whether the
lab and investigative work done is high quality or sloppy it doesn't matter as
long as the strong correlation between a crime being committed and someone
being punished remains.

Something something metrics and targets.

------
acomjean
I took a genomics class. We had a guest lecture by: Frederick R. Bieber about
medical Forenics. Fascinating stuff.

Its interesting the way they try to identify people is they pick 13 locations
(more as of this year, the article says 16 locations for england) then count
what are known as "Short tandem repeats"(STR). These STR markers exist on many
chromosomes and are short sequences that repeat, everyone has a different
count. (there is a standard for these locations in the US called CODIS:
[http://strbase.nist.gov/fbicore.htm](http://strbase.nist.gov/fbicore.htm))

If you have good reads the probability of a random match is in 1 in 594
trillion. Its complicated as the DNA can degrade and the reads can be not so
good.

Some places allow Forensic DNA analysis by data mining, in which case you may
find relatives of a criminal. Some states require felons DNA to be added to
the database. This can be searched though its controversial and familial
searches are blocked by some states.

One case helped by this was Lonnie Franklin Jr. aka the "grim sleeper" who
took a long time to apprehend.

[https://en.wikipedia.org/wiki/Grim_Sleeper](https://en.wikipedia.org/wiki/Grim_Sleeper)

"Police had found no exact match between DNA found at the crime scenes and any
of the profiles in California's DNA profile database, so they searched the
database for stored profiles that demonstrated sufficient similarity to allow
police to infer a familial relationship. They found similar DNA belonging to
Franklin's son, Christopher, who had been convicted of a felony weapons
charge. "

Exonerations are possible using dna too:
[http://www.brandeis.edu/investigate/innocence-
project/dennis...](http://www.brandeis.edu/investigate/innocence-
project/dennis-maher.html)

DNA analysis is just a tool, it can also lead to post conviction exonerations.
I think its best used a evidence for building a case, not having the whole
weight of the case on just DNA evidence.

------
libeclipse
I'm wondering if it could ever get to the point where you should never give
away your old clothes in case the next owner dies and you're incarcerated for
murder.

Incineration-As-A-Service anyone?

