Sunday, July 10, 2011

Casey Anthony's "CSI" Effect

The shock waves still continue to emanate from the Casey Anthony trial where the young Florida mother was acquitted of murdering her 3 year old daughter but convicted of the lesser offenses of lying to police.  Rendering a verdict in court cases is much like testing hypotheses in statistics.  The researcher (or the jury) makes a decision based on the data (aka evidence) that is available and based on the likelihood of this data (or evidence) being observed when the research hypothesis is assumed false (ie. presumed innocent until proven guilty).  This decision is later compared to some objective truth (which if you're religious only God and maybe the perpetrator would know for certain). Criminal trials are seldom as clear on guilt or innocence as that of Richard Poplawski.  There are two types of errors that can be made: the first is to put an innocent person in prison and the second is to let a guilty person go free.  The founding fathers considered the first error to be the more serious as Ms. Anthony can now never be tried again for this crime.
Criminologists have talked about a CSI effect where juries expect police and prosecutors to have detailed physical evidence tying the accused to the crime scene and the victim.  This may or may not have happened in this case, I haven't followed it that closely.  Of course in scientific research, the news media and the public is often far less critical of published research findings often latching on to them (especially when it supports what one already believes) unquestioningly.  In both of these cases one's emotions can override one's rational faculties when things like the death of a child are involved.

Jack the Ripper was never caught in the Victorian era at least partly because CSI tools like finger printing or DNA analysis were not available in the 19th century.  Arthur Conan Doyle started writing the Sherlock Holmes novels and short stories about the same time as Jack was active.  It may be a coincidence that Doyle's success with Holmes and the public's fear and frustration with Jack the Ripper but I doubt it.  Just as modern police hate shows like CSI I wonder what real Victorian detectives thought of Doyle's Holmes?  My hypothesis is that they sympathized with Dr. Watson.  Look for Holmes solving the Casley Anthony case soon on CSI.
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  1. About the Casey Anthony trial, was there any testimony about the presence/absence of water in the dead child's lungs ?

  2. I wasn't following the trial. This is a general posts about the effect of shows like CSI on real criminal trials.

  3. Probably not Marty, the body was so badly decomposed when found that a cause of death could not be determined. At least one juror stated afterwards that one of the reasons for the "not guilty" verdict was due to a cause of death being undetermined. After all, how can you find someone guilty of a murder when you cannot determine how someone died?

    As for the trial itself, I think the media hype helped guarantee a not guilty verdict. If the national spotlight had not been turned on what is, in essence, a local matter (and I'm looking right at you Nancy Grace)prosecutors might have tried the case on a lesser charge, securing a plea agreement, etc, rather than going for all the marbles with a murder indictment.

    Speaking of the CSI effect, I took a report on a theft from vehicle where the victim gathered up all the cigarette butts around her car and presented them to me for DNA testing!