Showing posts with label DNA Testing. Show all posts
Showing posts with label DNA Testing. Show all posts

Tuesday, October 18, 2011

A Rape Case In Sweden


by Andrea Campbell

I am never surprised at the results that can be achieved with forensic science. It is comforting to know that as time moves on, so do improvements in evidence collection and evaluation. Today’s story illustrates these ideas and even though it happened in Sweden, we are happy to see a righteous outcome.

High-Intensity UV Lamps
Body fluids are an important part of a crime scene, in murder and especially with sexually-based crimes. Since body fluids have properties that make them fluoresce under alternate light, it makes sense to walk the scene carefully with the light in hand and mark all the stains with cones or markers that may prove to be clues later on. The light won’t tell you what you’re looking at, but after collection and examination, you may get DNA and other readings.

The Rape in Sweden
On a cold day in Sweden, crime scene investigator Birgitta Jansson, who is with the Karlstad, Sweden police technical division, walked through the snow. It was dawn at about 7:20 in the morning and the sun was waiting to rise over the horizon. An outdoor scene, the crime was committed in a residential area near the center of town, and not far from a school. The case was an alleged rape and it took place at the corner of a hockey rink in a snow drift.

The snow left behind some obvious impressions: the shape of a human figure—arms, legs and torso—that were clear enough. In addition to the visual evidence were some Swedish coins that had fallen from the perpetrator’s pockets that were lodged deep in the snow. Blood was also found near the coins, and all were subsequently collected as evidence.

Investigators then used a high-intensity ultraviolet light to illuminate the scene, just as the sun was beginning to rise. Three spots, thought to be semen, were found in a 4 x 4-inch area.

“The light made the semen fluoresce in the snow, to the extent that I never thought possible,” said Jansson. “Actually, I was amazed that it worked. I never thought you could distinguish semen from snow with the help of a high-intensity UV light. And there was no doubt—the fluorescence was incredibly strong and clear. I have never seen anything like it.”

Jansson examined the glowing pieces more closely and found that they were now frozen liquid laying separate from the snow. They secured and collected those lumps of ice and packed them into bio bags, stored them in the freezer in the police car, in the hopes of sending the frozen liquid to the laboratory.

Back at the Laboratory
Once the lab examined the frozen, cube-like evidence it was clear that there were both semen and vaginal secretions. The sperm produced DNA and was ultimately matched to the vaginal swabs taken from the victim. The rapist was subsequently tried, convicted and sentenced.

The Fluids That Fluoresce
Semen, vaginal secretions, urine, sweat and saliva are all bodily fluids that will fluoresce under UV light. Urine is the easiest to detect, followed by semen, and the others will too, only more often very faintly.

Rehn, Lisel, “Semen fluoresced in the snow solved a rape case in Sweden,” Evidence Technology Magazine, July-August 2011, pp 24-25.
DNA photo: US National Library of Medicine 
photo (right): jah~


Monday, September 26, 2011

Now you see it … The Eyewitness Controversy


It happens in a flash, usually without warning, and certainly for victims and witnesses, without much in the way of preparation. One minute they could be minding their own business; the next they can be in the throes of a crime. Murder, rape, and robbery–you name it–crimes literally happen in the blink of an eye.

Just as quickly, a moment can change the trajectory of a defendant’s life. That moment is the moment they are identified as the one who did it. While courts and prosecutors have long given lip service of the magnitude of this issue, eyewitness misidentification has finally become a real issue that is finally being looked that’s to a historic ruling by New Jersey’s Supreme Court.

As a deputy district attorney in Los Angeles, I handled all kinds of cases with all kinds of evidence. Much of that evidence came from the witnesses and victims to the crime. Witnesses who often swore they could never forget the face of the bad guy. But could they? Really?  

Let's have some perspective here. The most heinous crimes out there–child abuse, sexual assault, rape, domestic violence, elder abuse, and stalking–are crimes that are perpetrated by someone whom the victim knows, and often knew well. These are the cases you hear about in the news. Less discussed are the “stranger” cases, where the victim and perpetrator have no connection, didn’t know each other, and were only brought together through some random (or not so random) senseless act of violence. These are the “ID” cases.

Witnesses are supposed to be considered just like any other type of evidence in a case --blood, sperm, fingerprints-- but they’re not. We all know that the truth is, juries love witnesses. Nothing persuades a jury more than the, (cue the theme music) “Law and Order” moment when a witness takes the stand, looks over, and points to the suspect and says, “There he is. He’s the one who did it.”

In every case, the prosecutor is trying to figure out whether they can make a case. And while we try not to put the pressure on victims to perform the reality, there is a great deal of importance in determining whether the witness can testify credibly, whether their story makes sense, and, more importantly, points to who did it.

The defense attorney, on the other hand, is trying to hold the prosecutor to the burden of proof the Constitution guarantees–that is, the prosecution must prove its case beyond a reasonable doubt. So, as a defense attorney, those words of the witnesses are not about simply making a case; they are about making darn sure you have the right dude.

In my defense work, I pride myself on acknowledging that a crime may, or assuredly did occur. However, I am going to make sure that the prosecutor can prove that the perp is my dude, and not some other dude or SODDI, the known acronym in the legal world for “some other dude did it” defense.

We all know about reliability issues with witnesses. Some have an axe to grind, some have a prior relationship, others have a criminal record or unsavory past, some are drug users, hookers–you name it. But credibility issues are one thing; witness reliability when they are otherwise credible adds a new wrinkle to the equation.

And this is a wrinkle that will really make a dent in criminal prosecutions and finally confirm what defense attorneys have been groaning about for years. And that is that eyewitness identification is inherently flawed. Make no mistake, the New Jersey high court’s ruling could forever change the way police use witnesses to identify bad guys. The US Supreme Court is going to weigh in on the entire issue for the first time since 1971.

Here’s what I’ve witnessed myself over the years: When witnesses say they are 100-percent sure, I’m 1000-percent sure they are not. Why? Our minds and our memories are far from perfect. Sometimes we can’t remember what we had for lunch yesterday. Think about what can happen when a crime is involved. Think about the fear, hate and all kinds of trauma involved here. The chance for unaffected memory is next to zero.

Now, let’s add on the impact of law enforcement. Let’s say you’re a rape victim. The cop who comes in to help you catch the rapist is going to have enormous influence on you. So, if he or she shows you a photo of the bad guy, chances are you will end up agreeing with the choice. I’m not suggesting this is a deliberate act, but it happens all the time. We are only now beginning to understand how a witness experiences and remembers events, faces and time.

The New Jersey Supreme Court Justice, which ruled in the case, said it best: “A vast body of scientific research about human memory has emerged. That body of work casts doubt on some commonly held views relating to memory.” 

Barry Scheck, founder of the Innocence Project and who is famous for using DNA to overturn wrongful convictions, released the following figures from the Project’s files. Of the first 250 wrongful convictions cases overturned by DNA evidence, 190, or 75 percent, involved eyewitnesses who turned out to be flat-out wrong.

Now the courts are finally acknowledging there are issues of eyewitness identification. The question is what is the solution? Prosecutors would like to say defense attorneys could simply argue their cases (but how?), some defense attorneys will argue for exclusion, suppression or limitation of the evidence altogether. Courts allow for experts to appear to testify about the inherent flaws, or even permit jury instructions that address the issues inherent to misidentification by guiding jurors through the process. All of these may be great solutions but they are fixes to a bad identification.

When a person is facing incarceration, loss of liberty and other collateral damages, after-the-fact fixes are just not good enough. We live in a country that forces prosecutors to meet their burden of proof.  Isn’t it time law enforcement be held to the standards that correspond to that heavy burden?

So what am I suggesting? I am suggesting we do something about identification at the critical moment when the initial interview and identification is happening. That is creating a standardized “best practice” system to account for the inherent issues of misidentification, lack of reliability and suggestibility. The simplest and easiest of these can be done right now with only the cost of a tape recorder. If police are required to tape the entire interview with each witness, victim, and suspect then at least everyone can hear verbatim what went down, how the interview was conducted, and how an ID occurred. It is a transparent option that at least will allow attorneys to argue and then jurors to decide for themselves if the identification was good or bunk. There are tons of other ways too, but in a budget-conscious society, one resistant to change, let's start simple with a $15 tape recorder.

If we clean up that part of the investigative chain, we’ll all be able to live with the results as the case makes its way through the system. Memories are flawed. Law enforcement can be too. Let’s remove as much of the human-error part as possible. It’s going to be a better result for justice, which is better for everyone.


Friday, February 25, 2011

DNA Manipulation


by Andrea Campbell

When technology gets better, there will always be someone who wants to defeat the system. It’s comforting to know that progress is continually being made in order to stay ahead of the criminals.

We’ve talked a lot about biometrics and DNA. These are thought of as irrefutable biological characteristics that help to define and identify just who we are. That’s why when I saw the headline, “DNA Paternity Test Almost Fooled,” I had to know more.

Who’s Your Daddy?

Paternity tests use DNA to allow people to discover their origins, such as who are my mother and father? DNA has longed been used for this process and there are reasons that someone would not want to be found—mainly child support payments. In 2007, someone found a way to confuse the identification system temporarily and it has now prompted a new methodology because of this person’s brash moves.

Apparently the fraud attempt was predicated by a DNA paternity test.

The paternity test is done just as one would do for a crime suspect—samples of saliva cells are collected from the mouth. In this particular case, Dr. José Antonio Lorente Acosta, Director of the Laboratory of Genetic Identification at the University of Granada, carries out forensic tests just like these as commissioned by the court in cases of paternity, and for the identification of possible criminals, or else to contribute to DNA databases such as in the case of trying to locate missing relatives.

In this 2007 case, epithelial cells were collected from the interior of the mouth by a person undergoing a paternity test, which gave an incongruous result. The research team questioned their procedure and found they had not changed anything. The suspect washed his mouth and, “... after repeating the analysis, there was only one possible conclusion: In the mouth of that man there was DNA from two different persons,” says Dr. Acosta. They, of course, arranged to meet the subject again and found out that shortly before he took the test, he mixed his saliva with someone else’s that he had concealed on his person in a small container, hoping to mislead detectives. As it turns out, the test was repeated and he was found to be the biological father in that particular case of judicial investigation. This case prompted a modification of all future tests, as now it would be compulsory for the donor to wash his mouth out, but this time in the presence of a witness.

The Grim Sleeper Case

A Los Angeles' serial killer who was thought to have killed at least 10 people, was caught by detectives who used a familial DNA search and that, and new databases, has made somewhat of a breakthrough. Only Colorado and California currently have laws specifically allowing the use of familial DNA match. The practice has drawn criticism from privacy advocates who fear that innocent family members will be targeted if they have the misfortune of being related to a criminal.

The research policy, however, is restricted to major violent crimes, and only after all other investigative methods have failed. Apparently the majority of the Grim Sleeper’s killings were committed in the 1980s. Unfortunately the crimes restarted after a 13-year absence, with the latest one occurring in 2007. This prompted Los Angeles' police to look for a “similar” DNA profile. Hoping they might find a relative for leads, after running several tests, some DNA was identified as the suspect’s son. The after-effects of this case and use of familial DNA will surely set precedents for its future use, as well as new policies as other states adopt the process. First published in Forensic Magazine.

Take That Robbers: DNA Mist

This new technology is fairly genius and was discovered in the Netherlands. We’ve all seen in films where the bank puts explosive dye packs in the money bag in order to mark the criminal after it explodes. They open the bag to get the money and are showered with indelible ink. Now there is a DNA spray mist! The applicator is positioned on the door of a bank or other business that has funds. Every person who enters is misted with a DNA spray that has no odor and is completely unnoticeable. The synthetic DNA compound settles onto hair, clothing and skin without knowledge. Of course, somewhere on this person is a trail that has a fluorescent marker that can be detected using ultraviolet light. Not only that, but the DNA can be made unique to a particular location. Good thinking that.

All photos are Clipart.com


Thursday, July 29, 2010

Free at Last, Free at Last


by Katherine Scardino

Is it my imagination, or are we reading too many stories about citizens in this country spending many years of their lives locked in a box in prison and then, decades later, some magic occurs and we learn the person is innocent?

In March a year ago, I wrote an article for Women in Crime Ink about Henry Skinner, who had been requesting DNA testing on the evidence in his case ever since his conviction in 1994. In March, there was an uproar over whether the evidence in his case should be subjected to DNA testing. My position last March, and today, is why in the hell not? What would it hurt? The cost of the lab testing is relatively small compared to the cost of years of feeding, clothing and guarding a prisoner -- or executing him. Even worse is the moral cost of execution if we were to later learn Mr. Skinner is indeed innocent.

The Supreme Court will listen to arguments in Skinner’s case within the next few months to determine whether to open a new avenue for convicts' access to evidence for DNA testing. But for Mr. Skinner, his time is up. This is his last chance; for him, it's life or death. We'll watch the Supreme Court on this case. Its decision could define the basic fairness of the law in the United States, or the lack of it.

This week, we released another innocent man who had spent 19 years in a Texas prison on a 1990 rape conviction. Allen Porter (right) walked out into the fresh air after a hearing in state court in which his nephew, Jimmy Hatton (currently serving time for this crime), and Perry Harrison (never charged in the crime) came forward to say that Mr. Porter was not a party to the crime, that they were the guilty ones. Where have they been for the last 19 years? Did they forget he was locked up in prison? What took them so long?

The ultimate problem is that once again, Texas screwed up. How many times does this have to happen before someone does something? My imagination can't encompass the emotion of hearing a cell door slam shut behind me, or of looking around the 10-foot-square box that would be my home for most of the rest of my life, let alone of knowing that I had not committed the crime for which I was convicted. I'd know that I'd told my lawyer -- over and over -- that I wasn't guilty. I told the prosecutor, the judge and jury. No one listened. No one believed me.

So here I am, alone and scared, wondering how I am going to convince just one person that I am innocent. All anyone has to do is test the evidence for DNA. With competent, efficient lab work, I could be exonerated. But my lawyer did not ask for the DNA testing. I don't understand why not. Where do I go from here?

Amazingly, this is happening more and more often, not less. Here’s a scary statistic: Since 1973, 138 people have been released from Death Rows across the United States after new evidence showed their legal, if not actual, innocence. Does that number get your attention? If all of us had done nothing on these 138 cases, these 138 people would now be dead. This has got to stop. We now have the technology to prove innocence in many cases.

Why is there ever an issue about DNA testing? Why would the prosecutor in every jurisdiction not test all the evidence? The evidence in every criminal case is in the hands and control of the State. Of course, the defense lawyer can request a DNA test by the State, or even get one done by their own forensics experts. But ultimately, the evidence is in the control of the State prosecution and the police. If justice is our goal, then test the damn evidence!

To give credit where it is due, the Harris County District Attorney's Office finally started an investigation in Mr. Porter’s case. They gave the case to a star in their office. Assistant District Attorney Baldwin Chin did something that seems to be a novelty nowadays -- investigate. Through his investigation, Mr. Chin learned that Mr. Porter may be an innocent man.

In an article this week, our elected district attorney said her office has a “sworn mission to serve justice.” She said “The integrity of the criminal justice system means everything. Wrongful convictions are a triple tragedy -- for the accused, for the victim and for society. The true criminal is free to continue to commit offenses.”

Well, Ms. District Attorney, I have a solution for permanently avoiding these embarrassing moments. Tell every one of your assistant DA’s that you will now require that all the evidence be DNA-tested. Period. Wouldn’t that put an end to the seemingly endless stream of stories about having to release, of all things, an innocent person from prison?