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A New Forensic Tool for Rape Cases?

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Rachel Feltman reports in the WaPo:

A new study suggests that the microbes present on pubic hair -- which vary from person to person -- could be used as evidence in sexual assault cases. This particular research is in its early stages, so you probably won't hear about genital microbes in a courtroom anytime soon. But the study is just one example of the effort to turn the incredible diversity of the bacteria that live on human beings into a high-tech forensic toolkit.
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The researchers, led by Silvana Tridico from Murdoch University, took scalp and pubic hair samples from seven individuals (three male and four female, with one co-habitating couple in the mix). While hair from the head had around 50 kinds of bacteria a pop, and seemed to be influenced by the environment, pubic hairs had over 70 kinds of bacteria each, which were highly individualized. That's in line with previous studies on the vaginal microbiome, which has shown an unexpected diversity distinguishing one individual from another.

"The advent of DNA profiling has resulted in an increase of sexual offenders using condoms, which they take away, post-assault," Tridico said in a statement. "The implication of this present study is that the transfer of bacteria between victim and offender, in rape cases, may provide a new way of linking the offender to the victim, in instances in which no human DNA is transferred."

Missing Data on Justifiable Homicides

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The quality of any study cannot be any better than the quality of its data.  Modern statistics computer programs can produce a dazzling array of colorful charts and graphs, but if the input data are faulty, it's all pretty nonsense.  As we used to say when I was an IT guy, "garbage in, garbage out."

The main source of data for people studying crime has long been the Uniform Crime Reports compiled by the FBI.  These numbers are initially reported by local police agencies.  There are some known problems and some controversies.  Collection and submission of data by the agencies is voluntary.  There are even charges of intentional manipulation in some cities.

Then there are the Supplemental Homicide Reports.  These provide much more detail on homicides, but compliance is even more spotty.  Rob Barry and Coulter Jones report in the WSJ that there are yawning gaps in the data on justifiable homicides by police.  For example, Fairfax County, Virginia, did not report justifiable homicides at all because, well, these are crime reports and justifiable homicides are not crimes.  Of 105 large police agencies contacted by the reporters, justifiable homicides from 35 of them did not appear in the FBI records at all.

What's a researcher to do?  You must know the limitations of your data.  I once started a project using the SHR where a key data point was the circumstance of the homicide.  I had to shelve it because so many cases had that data point missing that the input data were essentially worthless.  Bad research producing very wrong results can be done by people unaware of the limitations of their data.  Of course, if the researcher is actually an advocate seeking to bolster the Politically Correct position on a controversy, then truth doesn't matter.  Damn the limitations, full speed ahead!

Underreporting of Crime

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Last week I had this post on the Uniform Crime Reports, and a commenter noted that skepticism was in order due to underreporting by some police departments.  Across the pond there appears to be a major kerfuffle on this point.  David Barrett reports in the Telegraph:

Almost a million crimes a year are disappearing from official figures as chief constables attempt to meet targets, a study by the police watchdog has disclosed.

Its report exposed "indefensible" failures by forces to record crime accurately, and said that in some areas up to a third of crimes are being struck out of official records.

Her Majesty's Inspectorate of Constabulary said violent crimes and sex attacks were particularly vulnerable to being deleted under "inexcusably poor" systems.

Although the report stopped short of accusing police of widespread "fiddling" it said there was an "undercurrent of pressure not to record a crime across some forces" and "wrongful pressure" by managers.

It means violent criminals and even rapists are not investigated, potentially allowing offenders to strike again.
The FBI has finally come out with the 2013 statistics for Crime in the United States, almost two months later than last year.  The good news is that crime is down from 2012 about 5% in crimes per 100,000 population nationwide on both the violent (-5.1%) and property (-4.8%) scales.

Last month, we noted the good news that California crime was down, but we were interested in seeing the national figures for comparison to sort out national trends from possible effects of California's sentencing "realignment."  Last year's post making that comparison is here.

We look at property crime as the primary indicator, as persons convicted of violent crimes, either for the present offense or as priors, are not eligible to be shunted off to county jail under realignment.  Many property crime convicts are, and given that the jails are overcrowded in most counties they either get released early or they push out other inmates for early release, likely other property crime convicts.

California's overall property crime rate is down less than the national average, -3.8% versus -4.8%.  Auto theft is the category tracked by the FBI that is most likely to be affected by realignment, because all auto thefts in 2013 (pre-Prop. 47) were realignment-eligible felonies, while other categories are mixed eligible/ineligible or felony/misdemeanor.  Consistent with the realignment-effect hypothesis, California's improvement in auto theft lagged considerably behind the nation, -2.8% versus -4.0%.

Comparing 2010, the last full year before realignment, with 2013, property crime has dropped 7.2% in the nation while rising slightly, 0.8%, in California.  Auto theft is down 7.3% nationally but up 5.3% in California.

Political Bias in Psychology?

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In the latest issue of the New Yorker, Maria Konnikova has a story that asks, is the field of psychology politically biased?  As the popular saying goes, to ask the question is to answer it.  Anyone who has spent any time within the field of psychology knows, if they're being honest, that the answer to that question is an emphatic "yes" all around.  But what is the nature of the bias? 

Studies and Coding

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In almost every debate about policy, someone asserts confidently that "studies show" whatever supports their position.  However, what "studies show" is not necessarily so.  Occasionally on this blog we highlight why the neat little bottom line result that makes the newspaper may not be true.  Sometimes, the reason involves inherent difficulties in studying a particular area, fully disclosed by the researcher, but deemed too complicated for a newspaper article.  Sometimes it is simple sloppiness on the part of the researcher.  In the worst case, it represents intentional manipulation by an agenda-driven researcher intent on producing "evidence" for a predetermined position.

Eugene Volokh has this comment at VC on a study that purports to show that Supreme Court Justices are more likely to vote for protection of a speaker in First Amendment cases if they are ideologically aligned with that speaker.

Before studiers can crunch numbers, they have to reduce real-world realities to simple numbers.  This is called coding and there is a lot of opportunity for either error or distortion in this process.
Wayne Hall of the University of Queensland (Australia) Centre for Youth Substance Abuse Research has a monograph with the above title in the journal Addiction.  Here is the abstract:

Aims:  To examine changes in the evidence on the adverse health effects of cannabis since 1993. Methods:  A comparison of the evidence in 1993 with the evidence and interpretation of the same health outcomes in 2013. Results:  Research in the past 20 years has shown that driving while cannabis-impaired approximately doubles car crash risk and that around one in 10 regular cannabis users develop dependence. Regular cannabis use in adolescence approximately doubles the risks of early school-leaving and of cognitive impairment and psychoses in adulthood. Regular cannabis use in adolescence is also associated strongly with the use of other illicit drugs. These associations persist after controlling for plausible confounding variables in longitudinal studies. This suggests that cannabis use is a contributory cause of these outcomes but some researchers still argue that these relationships are explained by shared causes or risk factors. Cannabis smoking probably increases cardiovascular disease risk in middle-aged adults but its effects on respiratory function and respiratory cancer remain unclear, because most cannabis smokers have smoked or still smoke tobacco. Conclusions: The epidemiological literature in the past 20 years shows that cannabis use increases the risk of accidents and can produce dependence, and that there are consistent associations between regular cannabis use and poor psychosocial outcomes and mental health in adulthood.
In olden times, proponents of marijuana prohibition ridiculously exaggerated its harmful effects, a campaign reaching its unintentionally hilarious peak in the film Reefer Madness.  Today, proponents of legalization engage in equal and opposite propaganda, trying to convince us that marijuana is completely harmless.  I call this campaign Reverse Reefer Madness.  CJLF takes no position on the legalization issue, but we should be basing our decisions on science, not propaganda.  Hall says:

Our best estimate is that the risk of developing a psychosis doubles from approximately 7 in 1000 in nonusers [102] to 14 in 1000 among regular cannabis users.
Schizophrenia is a terrible disease.  It wrecks people's lives.  It has a profound impact on the lives of people close to them.  Doubling the risk is no trivial matter.

Hat tip to Michael Tremoglie, who has this article at Main Street.
The Heritage Foundation is no longer the devil it once was on the Left. Recently, Heritage has come out strongly for reforming mandatory sentences, and against over-criminalization and over-federalization of law.  

I am sympathetic to the latter and skeptical to the former, though I know sentencing reform is backed by very good people and friends like John Malcolm and Paul Larkin at Heritage and Sen. Ted Cruz.  Of course it also has the backing of George Soros, the NACDL and the SEIU, which you'd think would scare off anyone to the right of Valerie Jarrett.

This prelude is necessary to equip my friends at Heritage to duck the brickbats headed their way to the effect that, "I always knew you were fascists after all"  -- brickbats sure to blacken the sky when Heritage reports that its scholar's extensive study shows: 

Based on data from all 50 states from 1978 to 1997, each state execution deters...

Of course deterring the murder of innocent people by executing stone cold guilty ones has never been a big priority with the Left, which has preoccupied itself instead peddling the flabbergastingly false story that blacks are in mortal danger from rampaging whites.  They might want to try again, though self-correction  -- or any other kind for that matter  --  doesn't wear well with the pious (when not snarky) Mark Oslers of the world.  

Still, for those who haven't had their brains fried on critical legal studies and other forms of Amerika Stinks theory, the Heritage Study results showing the death penalty's deterrent value will be of more than a little interest.

Good News on California Crime Rates

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California property crimes per 100k population totaled 2,665.5 in 2013, a 3% drop from the 2012 figure although still above the rate before the realignment law went into effect.  Even better, the rate of violent crimes, less affected by that law, is down to a level not seen since 1967.  The California Attorney General released the annual Crime in California report September 26.

Comparison with national figures would be very interesting to help illuminate how much of this is local and how much reflects national trends, but the FBI still hasn't published the 2013 Crime in the United States.

Mass Shootings

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The FBI has released a report titled A Study of Active Shooter Incidents in the United States Between 2000 and 2013.  Devlin Barrett has this story for the WSJ. 

How were the incidents "resolved"?

The National Crime Victimization Survey, which showed a bump up for 2012, showed a reversion back for 2013. The graph to the left is from the Bureau of Justice Statistics Report, Criminal Victimization, 2013.

Update:  BJS issued a correction September 19.  There was a problem with the scale on the original figure.  I have pasted in the corrected figure.

The title of this post is the headline of a story by Geoffrey Mohan in the Los Angeles Times.  He reports on "a 10-year study that [was designed to] compare how children would fare under prolonged therapy and tutoring aimed at improving social and cognitive skills, and whether their adult fates would differ from similar children who did not participate."
Phillip Reese has this post at the Sacramento Bee, noting a disturbingly sharp disparity in the arrest rate for one group in California, a rate nearly triple the state average.

It's the Culture, Continued

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Persons of sense have known for a long time that the primary "root cause" of crime is culture.  Kids growing up are subject to influence from parents, peers, schools, and popular media.  These influences instill in the growing kids either an attitude that (1) they should "do the right thing" in obeying rules (in all but extreme circumstances) and respecting the rights of others or (2) it's every person for himself and they should take whatever they can get away with.

Empirical validation of theories is difficult in social sciences because we generally cannot do controlled experiments.  That is why, for example, much of the "evidence" touted for rehabilitation programs is tainted by selection bias, as noted in posts last February here and here

Every once in a while, though, we get a "natural experiment" where a comparison becomes available between two groups that do or do not receive some "treatment" or "intervention" selected in a way that gives us increased confidence that the "treatment" and not the selection of the groups is the reason for the difference in outcomes.

One such "natural experiment" is forthcoming in the next issue of Pediatrics.  It is titled, "Successful Schools and Risky Behaviors Among Low-Income Adolescents."  The abstract is here and is copied at the end of this post.  The AAP press release is here.  AP has this story.

The thrust of the story is that kids randomly selected to go to better schools have a variety of better outcomes, including reduced gang membership.

More on Corrupt Peer Review

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Mary Kissel of the WSJ has a video interview with James Taranto on the peer review corruption scandal, similar to Taranto's column noted earlier

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