Archive for March, 2011
If it’s true, we would then have favorite jeans posthumously. Would that be too cool or simply bizarre? Either way, it may soon be true! Scottish researchers are looking at ways to recover “fingerprint ridge detail and impressions from fabrics”. Doing so has been an elusive goal and the success has come with a technique called vacuum metal deposition (VMD). Basically, gold and zinc is used to recover the fingerprint mark.
Joanna Fraser, a forensic sciences researcher at the University of Abertay, Dundee, said: “The research uses fine layers of metals to display fingerprints people may have left on fabrics, something which is far harder to do with soft surfaces. The technique has been around since the 1970s and is used on many surfaces but was never widely used on fabrics.
“We take these fabrics, place them in a vacuum chamber, then heat up gold to evaporate it and spread a fine film over the fabric. We then heat up zinc, which attaches to the gold where there are no fingerprint residues. This helps reveal the fingerprint — where contact has been made we see the original fabric, where there was no contact we’re left with the grey colour of the metal film.”
She added: “One way of explaining it is like a photographic negative, where colours show up as their opposites. Here the fingerprint ridges show through as clear fabric, but where there are no ridges we see the distinctive grey colour of the metal.
“Previously it had proved difficult to reveal a clear fingerprint on fabric, but we’ve shown that this is now possible. This is great, but the challenge is to develop this further and confirm its effectiveness.”
So, for example, if your favorite jeans had two handprints on the butt—maybe you were shoved off the balcony as opposed to jumping. Or—if scientists find handprints or fingerprints on your favorite jeans—they know to target those areas for further DNA evidence.
There is nothing like a good pair of jeans. Overall, though, I can’t say I’m going to sleep better for knowing this.
Fraser J, Sturrock K, Deacon P, Bleay S, & Bremner DH (2010). Visualisation of fingermarks and grab impressions on fabrics. Part 1: Gold/zinc vacuum metal deposition. Forensic science international PMID: 21126838
Wouldn’t it be handy to be able to predict the future behavior of others? Not to mention kind of disturbing? Like in the 2002 film Minority Report. There are times we have to try—like in assessing future dangerousness for those eligible for parole. And, in those cases, when we are wrong, bad bad things can happen. In the case of the release of Domenic Cinelli, the Massachusetts parole board made a tragic decision. There is a fascinating article over at the Boston Globe on the story.
“There has been a strong move toward the use of risk assessment instruments in the criminal justice system in recent years,” said John Monahan, a psychologist at the University of Virginia Law School who has been studying models of prediction since the 1970s. “The science of risk assessment is much better now than it was 20 years ago.”
Historically, our efforts to predict the future have included phrenology (identifying delinquent tendencies through feeling head bumps and skull shapes). That didn’t work so well. Now there are tests that measure character traits and individual experiences to identify risk factors for the person returning to criminal activity. There are now more than 120 such measures. (Here, as an example, is the Violence Risk Appraisal Guide [VRAG] and a link to the COMPAS site.)
The measures include things like past behavior (long the best predictor of future behavior) and age (older people are less likely to reoffend than younger people) but also other intriguing variables:
If your victim was female you are less likely to re-offend than if your victim was male.
Emotional health (i.e., depression, anxiety or low self-esteem) does not predict future behavior).
Murderers are less likely to reoffend than those that merely injured their victims.
Why the instruments work (or don’t work) is a matter of debate. Some of the researchers say people don’t change and their risk factors stay the same. Others say treatment can make a difference. Others (specifically, Bernard Harcourt at the University of Chicago) say we are basically categorizing by race even though the variable of ‘race’ is studiously avoided—other questions serve as proxies for race. So the question becomes one of whether you believe in the power of rehabilitation (or perhaps redemption).
Even harder questions may lie ahead. Berk, the University of Pennsylvania professor, said that as the data available to researchers get better, and the algorithms that are used to analyze it improve, we may find ourselves staring at uncomfortable predictions that leave us at a loss as to what to do with them. Berk’s method is to take into account as much data about people as is available — even if there’s no reason to think it would correlate with crime — and let massively powerful computers figure out what’s useful and what isn’t. Conceivably, these computers could discover that predictions could be made using someone’s shoe size and the kind of car their parents drove when they were kids.
“This is the nightmare that I have,” Berk said. “Supposing I am able to tell a mother that her 8-year-old has a one in three chance of committing a homicide by age 18. What the hell do I do with that information? What do the various social services do with that information? I don’t know.”
Maybe this predicting the future thing isn’t such a good idea after all.
Harris, G.T. & Rice, M.E. (2010). Assessment of risk and dangerousness in adults. In J. Brown & E.A. Campbell (Eds.) Cambridge handbook of forensic psychology. (pp. 299-306). New York: Cambridge University Press.
HARRIS, G., RICE, M., & QUINSEY, V. (1993). Violent Recidivism of Mentally Disordered Offenders: The Development of a Statistical Prediction Instrument Criminal Justice and Behavior, 20 (4), 315-335 DOI: 10.1177/0093854893020004001
There’s been a lot of finger pointing among political factions regarding the blame for the negative tone of political discourse. Democrats say it’s the Republicans. Republicans say it’s the Democrats. And the Tea Party says it’s the status quo (which likely means everyone but them!). Good thing we have researchers to resolve the issue. Turns out it really is everyone’s fault. What a surprise.
“The term “outrage talk” refers to a form of political discourse involving efforts to provoke visceral responses, such as anger, righteousness, fear or moral indignation, through the use of overgeneralizations, sensationalism, misleading or patently inaccurate information, ad hominem attacks and partial truths about opponents.
They looked at a 10-week period during the Spring of 2009 and examined “evening cable TV, national radio talk shows, ideological political blogs and mainstream newspaper columns for 13 variables, such as insulting language, name calling and misrepresentative exaggeration.”
What they found is disturbing. “Outrage talk” is hardly rare. It is the norm. Overwhelmingly the norm. 89.6% of the cases sampled reflected at least one outrage incident. But if we look at certain arenas, it gets even worse. Television (100%), radio talk shows (98.8%) are leading instigators while blog posts fall behind (82.8%). So they knew (and now we know) that “outrage talk” is common. But who does it most?
“Our data indicate that the right uses decidedly more outrage speech than the left. Taken as a whole, liberal content is quite nasty in character, following the outrage model of emotional, dramatic and judgment-laden speech. Conservatives, however, are even nastier.”
The researchers go on to say that even though liberals and conservatives don’t talk this way equally—they do it remarkably similarly. And newspapers are not immune to this phenomenon. When comparing newspaper columnists from 1955 (the civil rights movement) and 1975 (Vietnam protests and Watergate) to now—they found “outrage talk” was virtually absent from newspaper columns. Not any longer. Newspaper columns were found to contain almost 6 instances (5.76%) of “outrage talk” per column. It’s a sad reflection of current realities, political polarization and the rush for ratings and circulation.
It’s hard to say if the ‘mean’ debates and corresponding media coverage are really making us more fearful but there is also research that would seem to support that notion. Crime rates have actually declined in the past twenty years but it would be hard to know that from media coverage. We are more afraid with less reason to be afraid.
“One possible reason fear of crime remains high is that powerful people have an incentive to ring the alarms anyway. Politicians score points by promising to get “tough on crime,” even after those efforts pay off and crime levels hit historic lows. Media play up only the most horrifying deeds. The result is a skewed perception of how dangerous the world is. It’s telling, though, that most people believe the danger is not on their doorstep, but beyond it. Fewer people say crime is up when asked about their area than when asked about the whole country.
Another reason for the perception gap is the constant sense that things are getting worse. Only during one short period in the last 20 years have Americans thought there was less crime than in the past. That was in the two years after Sept. 11, 2001. “People were so positive about America that I think the enemy was perceived to be much more outside the country than inside the country,” a Gallup pollster told the Boston Globe.
Keep in mind, too, that perceptions of crime lag behind crime itself. Crime went down for several years starting in 1991, but fear remained high. “That was the nastiest and most fearful period in history,” says Zimring. Congress passed a federal “truth in sentencing” law in 1994. About half of the states passed “three strikes” laws to punish habitual offenders. All this, even though crime was already on the decline.“
Most of us know that eye-witnesses are simply notoriously inaccurate but there is some new work out there you should know about. First up, new information on cross-racial identification and then some intriguing information about familiar places and counter-intuitive errors.
There’s a large body of research on the inaccuracy of cross-racial identification. Recently a New York task force advocated the standardization of police lineups and suspect photo arrays to cut down inaccurate identification. They made these recommendations following a review of the research on cross-racial identification:
In an examination of cross-racial identification errors in criminal cases, Cornell law professor Sheri Lynn Johnson in a 1984 paper listed a series of earlier laboratory studies showing the so-called “own-race phenomenon,” where recognition rates could differ by 30 percent. They showed whites were significantly less able to recognize black or Asian faces, with other studies showing somewhat similar results for blacks and Asians.
For those of us who have followed the research on mistakes in cross-racial identification—this is a very good idea. You can review the task force report here.
Familiarity breeds mistakes:
You would think that testifying about what happened in an area very familiar to you would be a piece of cake. But no! The more familiar we are with a particular area (like a college campus, for example) the more biased (and inaccurate) we are about spatial memory. If you are more familiar with the northern area of your neighborhood or campus—you see the southern area as more distant and foreign than it actually is on a map.
We actually tend to be less biased (more objective) when we are newer to an area and more biased as our time spent increases (and therefore, as our familiarity grows). The researchers are not clear on how this bias occurs, but believe part of it occurs as you take on a “cultural identity” as, for example, a ‘northsider’ or a southsider’. This research has interesting implications for witness preparation as well as for the issue of how to make your client more like jurors. You’ll probably hear more from us on this one.
Uttal DH, Friedman A, Hand LL, & Warren C (2010). Learning fine-grained and category information in navigable real-world space. Memory & cognition, 38 (8), 1026-40 PMID: 21156867
We know that listening to someone with a foreign accent makes us more biased. As we blogged earlier—when we listen to someone speaking with an accent, we tend to view them as dishonest/not truthful. The heavier the accent, the worse it gets in terms of our assessment of the person’s truthfulness. Or at least some people do. Not you or me. But there is hope for those who have clients or witnesses with heavy accents.
Recent research out of Ball State University gives us information that you might use to help discredit eyewitness identification when the eyewitness is listening to heavily accented speech. We have to work harder to process and understand accented speech. As it happens, we have to work so hard to interpret accented speech that we don’t ‘see’ quite as well. [Oddly enough, there is a Facebook group for those that can’t hear when they don’t have their glasses on but that’s another issue.]
Because we have to work so hard to listen to and understand accented speech our memory for the speaker’s appearance can be impaired.
When direct comparisons were made between a perpetrator with an accent and one without an accent, researchers found that witnesses provided a significantly poorer physical description and were less able to accurately identify the perpetrator’s voice.
The more detailed the information spoken, the less accurate the witnesses were in reporting correct details about the perpetrator’s appearance.
And finally, the more threatening the message, the less accuracy in reporting the perpetrator’s appearance.
And just for fun, here’s an example of how the researchers varied the experimental script to make it a ‘low threat’ versus a ‘high threat’ situation. [The text in bold font was added to vary the low threat versus high threat conditions.]
I have a gun in my jacket, so do what I tell you or I swear I’ll splatter your brains all over this office. I have an accomplice who’s standing in the lobby near your security guard right now. He will kill the guard and start shooting customers if you activate the alarm. You will leave your office and turn left. Go to the loan officer’s cubicle and tell her you’re going to lunch. I’ll be watching, so don’t say anything else or both of you will leave this bank in body bags. Then walk back past your office and go to the vault. Open it and go inside. I’ll give you two large cloth bags. Fill them three fourths of the way with cash and then tie the drawstrings. Now listen carefully or I’ll kill you. Carry the bags out of the vault and turn right. I’ll follow you. Go out the east door to the parking lot and look for a dark blue Ford truck. Approach from the front and give the money to the driver. Then walk over to the sign by the street that says ‘exit only’ and stand there. Don’t move until after we have driven away. If you follow these directions, no one will get hurt.
So, a thicker accent, a detailed communication and a scary communication combine to dim our ability to recall someone’s appearance. We thought you might want to know that.
Pickel, K., & Staller, J. (2011). A perpetrator’s accent impairs witness’ memory for physical appearance. Law and Human Behavior