forensic science

Familial Searching Solves Cold Cases—At What Cost?

Posted on by Darcia Schweitzer

A cold case that had stumped investigators for nearly 41 years was solved last month. The 1976 sexual assault and murder of Karen Klass, ex-wife of Righteous Brother’s singer Bill Medley, shocked her Hermosa Beach, CA community and captured the public interest. Failing to make any arrests for decades, detectives were able to use DNA evidence to eliminate suspects in 1999 but were unable to find a database match. In 2011, investigators decided to try a new technique called a familial search and, after a few attempts, successfully identified the perpetrator.

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Familial searching (FS) involves taking a DNA profile obtained from a crime scene and comparing it to profiles in CODIS and other databases to identify male relatives. The DNA profile of an immediate family member, such as a sibling, parent or child, can provide a match that generates new leads for law enforcement. Detectives can then collect additional evidence to narrow down that new pool of individuals to a single suspect.

Last May I wrote a blog featuring a Q & A about FS provided by Mr. Rockne Harmon, a respected member of the forensic community and passionate advocate for FS. Supporters, like Harmon, and opponents agree that this method of obtaining matches to DNA evidence has demonstrated scientific precision and successful outcomes, as in the Klass case. However, it is still considered controversial and most states have not implemented specific policies regarding the application of FS to criminal investigations. So why isn’t the use of FS more widespread?

Continue reading “Familial Searching Solves Cold Cases—At What Cost?”

Toilet Paper: The Newest Tool in the Fight Against Crime

Posted on by Terri Sundquist

A roll of toilet paperIn July of 2009, the bodies of 43-year-old Alan Grna and his 85-year-old mother Julianna were discovered in their Ohio home—both victims of a violent assault. The lead detective in the case called in the Ohio Bureau of Criminal Identification and Investigation (BCI) to collect evidence from the crime scene, evidence that would lead them to the man who was eventually convicted of their murders. One of the key pieces of evidence was a roll of toilet paper.
Continue reading “Toilet Paper: The Newest Tool in the Fight Against Crime”

Poisoners and Scientists

Posted on by Isobel Maciver

If you eat enough silver, you will turn blue, but it probably won’t kill you.

In the 1920s, you could buy energy drinks and cosmetics containing radium. Because of its beneficial effects on tumors, it was believed to be healthy.

Arsenic was once known as “the inheritance powder”, because it was so commonly used to eliminate relatives who stayed alive too long.

In the 1930s the poison thallium was used in depilatory creams, because of its excellent ability to make hair fall out, but also because of its ability to lend a beautiful pale luster to the skin.

These are just a few of the fascinating facts and stories you can find in “The Poisoner’s Handbook”, by Deborah Blum Continue reading “Poisoners and Scientists”

A Scientific Explanation for Spontaneous Human Combustion

Posted on by Terri Sundquist

FlamesThe phenomenon dubbed “spontaneous human combustion” (SHC) has been described in the medical and scientific literature for centuries, dating back to the late 17th century. SHC also has appeared in fictional literature by authors such as Charles Dickens and Herman Melville. There has been no conclusive scientific proof to explain how SHC happens—how human bodies, which are about 75% water, can ignite (supposedly spontaneously, hence the name) and burn at temperatures high enough to destroy bones, muscles and other soft tissues while leaving material in the immediate vicinity relatively untouched by the fire. Cases of SHC are rare, making it difficult to determine a cause. In a 2002 Journal of Forensic Science paper (1), the author estimated that there were only approximately 200 cases worldwide since the 17th century.

Recently, a case that has all of the hallmarks of SHC was reported in the Journal of Forensic Science (2), causing the authors to revisit the topic, list the commonalities of apparent SHC cases and re-iterate the current hypothesis that might explain this bizarre phenomenon. Continue reading “A Scientific Explanation for Spontaneous Human Combustion”

Not My Shade of DNA

Posted on by Terri Sundquist

LipstickDNA testing is providing some answers in a nine-month campaign of hate and revenge involving two British women: a wife and her husband’s mistress. Between May of 2010 and February of 2011, the wife was stabbed in the stomach with a screwdriver, had bleach thrown in her face, received death threats in the mail, been the victim of an arson attack and had a threatening message written on her apartment window in lipstick. She blamed the mistress in her reports to police. As a result, the mistress had been arrested numerous times and spent 20 hours in police custody despite her assertions that she was not involved in any of the attacks. The situation became so maddening that her family started a diary of her whereabouts to help prove her innocence.

Hoping to find some physical evidence that might shed some light on the events, police examined the evidence in the case more closely. This included DNA analysis of the lipstick used to write the threatening message and saliva used to seal the envelope containing the death threats. The results of the DNA analysis were shocking. Continue reading “Not My Shade of DNA”

How to Catch a Serial Killer

Posted on by Terri Sundquist

A Lear jet“[I]deas about who killed whom does not come to the criminal profiler in flashes of insight, nor does a group of FBI profilers fly around the country in a Lear jet and solve heinous murders within a few days with the help of a computer genius back in Quantico who seemingly has unlimited resources and who admittedly conducts illegal hacking into data banks that are highly confidential.”

This excerpt from a recent Forensic Science International paper (1) pokes fun at criminal profiling as portrayed on television shows such as Criminal Minds. However, this is just another example of Hollywood producers embellishing reality and stretching the truth to try to increase the entertainment value. [To learn about how the television show CSI has warped public perception of the forensic sciences, check out The Reality of Crime Scene Investigation. Part I: Common Myths].

So, if these Criminal Minds and CSI approaches to catching murderers aren’t accurate, how do law enforcement officers identify killers and bring them to justice? Continue reading “How to Catch a Serial Killer”

Was Dr. Crippen Innocent After All? New Forensic Evidence 100 Years After his Execution

Posted on by Terri Sundquist

The past few decades have seen amazing advances in forensic science that are instrumental in analyzing DNA evidence to put perpetrators of crimes behind bars and exonerate people convicted of crimes that they did not commit. [Read William Dillon’s story of wrongful conviction].

Unfortunately for some people, these techniques were developed too late. One of those people was Dr. Hawley Harvey Crippen, who was accused and convicted of killing his wife Cora in 1910 using the forensic techniques available at the time. Until the very day of his execution, Dr. Crippen insisted that he was innocent, and now there is strong DNA evidence to support his claim. Recently, forensic scientists from Michigan State University analyzed DNA evidence in this case and published their results in the Journal of Forensic Science (1): The human remains that were so instrumental in Dr. Crippen’s conviction were not those of his wife.

Continue reading “Was Dr. Crippen Innocent After All? New Forensic Evidence 100 Years After his Execution”

The Reality of Crime Scene Investigation. Part II: The CSI Effect in the Courtroom

Posted on by Terri Sundquist

Judge talking to a lawerIn a recent paper, Evan Durnal from the Criminal Justice Department at the University of Central Missouri listed common myths that are created and perpetuated by crime scene investigation (CSI) television shows and summarized the effects of these shows on the judicial system (1). In part I of this two-part blog entry, I presented Durnal’s four categories of myths about crime scene investigation. In part II, I discuss the effects of these television shows on the judicial system, including jurors, prosecutors, defense attorneys, law enforcement officials and the criminals themselves.

In his paper, Durnal lists four main categories of myths: capabilities, roles and responsibilities, evidence and schedule. These myths all influence jurors’ expectations in the courtroom and affect the roles, responsibilities and tactics of judges, attorneys and law enforcement officials. Durnal describes it thusly “Nearly all definitions of the [CSI] effect stem from and refer to the impact that CSI and related shows have on the ability of trial juries to objectively hear testimony and make decisions without biasing those decisions on information obtained outside the courtroom proceedings”. He lists a number of examples demonstrating the CSI effect, originally published by Willing (2), including: Continue reading “The Reality of Crime Scene Investigation. Part II: The CSI Effect in the Courtroom”