Sum it Up! #50

Sum it up: k-9 RoccoSum it Up! #50 starts with the tragic news that K-9 Rocco was stabbed to death. From the Philly: “Rocco, an 8-year-old German shepherd, was wounded Tuesday while helping take an armed suspect into custody in the Lawrenceville neighborhood. He has been credited with saving the lives of his handler and two other officers on the scene.” R.I.P. Rocco

Elsevier has a great article online “Why forensic odontology fails; an ongoing innocence project case.” Here is the opening of the article: “For more than 30 years in the United States, bite mark evidence has been routinely used to identify the perpetrators of violent crime by “matching” a suspect’s teeth to an impression on the victim’s skin. But bite mark analysis is not based on scientific research. The ongoing case of Gerard Richardson, who was recently released from prison in New Jersey, shows why bite mark analysis should not be used as evidence of guilt at a criminal trial.”

The article explains the 1994 case of Monica Reyes. Monica was found dead in a ditch along Old Stagecoach Road in Bernards Township, Feb. 25, 1994. Cause of death was multiple blunt force traumas to the head. In the November 1995 trial against Gerard Richardson, a critical piece of evidence offered by the prosecution was an analysis of the bite mark found on Reyes’ lower back. A forensic odontologist said the bite mark matched Richardson’s teeth. The defense expert testified it did not. When tested, the bite mark swab did not contain Richardson’s DNA. It only contained female DNA. Later it turned out that the specimen had been contaminated with an analyst’s DNA during testing. In 2011, new tests revealed male DNA on that same part of the bite mark swab. However, it excluded Richardson as a match.

The article ends with a call for reform. Highly recommended reading!

Another great find concerns am article about blood spatter on the blog Narratively. In the post “Sultan of Spatter” Dr. Donald Johnson outlines how he wants to bring crime scene blood stains and forensic science into the iPad age.

As a rule, impact angles are considered to be accurate within five to seven degrees.” The current trigonometric math model doesn’t consider air drag, gravity or room temperature when determining the flight path of a blood droplet; it assumes that the blood drops traveled in a straight line. Johnson and his engineering team are seeking to identify a better math model that will take all those variables into consideration.” 

Last but not least, the next #crimechat is on Valentine’s Day so you can tell me all about your most favourite unsolved mystery over lunch. Join me on Twitter on February 14 from 12-1pm EST.

Cheers!