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December 31, 2010

DNA, SANE Nurse - Expert Analysis in Colorado Sexual Assault Conviction May Have Made the Difference


The Following verdict in a Colorado Sexual Assault Trial demonstrates the many levels of testimony that can be admitted in a trial .. it is instructive at many levels for that reason

Jury convicts Valdez of sex crimes Thursday, Dec 30th, 2010

DEL NORTE, Colorado ・A Rio Grande County District Court jury deliberated for four hours before the criminal incest trial of Arthur Valdez ended with a verdict of guilty on two counts.

Valdez, 39, has an address in Alamosa and is reportedly a registered sex offender with a previous felony conviction, which qualifies him for enhanced sentencing for a repeat offense.
A hearing regarding the habitual sentencing enhancer for Valdez will be held Jan. 12, 2011. His sentencing is scheduled for Feb. 9.

Assistant District Attorney Crista Maestas told the jury that, throughout the trial, they had heard testimony from the alleged victim; school officials who knew the young woman better than her own family did; expert testimony from a Colorado Bureau of Investigation (CBI) criminal laboratory analyst; the Sexual Assault Nurse Expert (SANE) who performed a physical exam on the girl, and from others who investigated the case.

Responding to defense allegations that the girl had lied and set her father up as an act of revenge, Maestas asked the jury, What did she (the alleged victim) get from this?・

He ended up homeless, she graduated and not a single family member was there. She had to undergo a horrible exam and tell her story repeatedly "why in the world would she possibly make this up?"

The defense claimed the alleged victim wanted revenge because she didn't have the relationship she wanted to have with her father. The defense admitted Valdez was not a model father to his daughter, but said he was not on trial for that. They claimed Valdez thought his daughter would try to set him up and deliberately stayed away from her or had others with him when they were together.

Defense attorneys claimed a CBI Analyst findings from a sample on a pair of underwear was inconclusive for bodily fluids and only uncovered skin cells.

Maestas countered that the analyst reported that they were enucleated cells of some sort. The CBI also reported that the YSTR analysis matched all 11 sites. The YSTR is a specific DNA match test for the presence of the male or Y chromosome and the identity of the Y.

With all sites matching, the analyst reported the DNA sample could only have come from the defendant or one of his paternal male relatives.


H. Michael's Take

In this case you have a classic frontal attack on the victim's credibilit. The defense lawyer did an excellent job and had much to work with in this case in the area of witness credibility. However, notice the prosecution's expert forensic evidence attack that went unrebutted for the most part.

The SANE nurse:

Sexual Assault Nurse Examiner (SANE) Programs were created whereby specially trained forensic nurses provide 24-hours-a-day, first-response care to sexual assault patients in either hospital or non-hospital settings.

These nurses go well beyond the care of the alleged victims - they collect forensic evidence traditionally performed in hospital emergency departments. They document injuries and physical evidence, they document the alleged victim's statements and their demeanor

The CBI - Colorado Bureau of Investigation Testimony

Here - even though the sample of the DNA evidence was questiionable - it was admitted and was most likely used by the jury to push the case over the beyond a reasonable doubt standard

Bottom Line: Defending an allegation of sexual assault is difficult under the best of circumstances -- defending such a case without expert testimony to counter the State of Colorado's nearly endless resources -- is daunting -- a war chest of defense funds is often necessary to mount an effective defense at times.

September 1, 2010

The Emerging Role of Forensic Analysis of Evidence

The airwaves are full of television shows demonstrating the vital relationship between science and truth in the criminal justice system. CSI, NCIS, Etc...

The following story demonsrates the life and death relationhip between achieving truth through science and correcting flaws in an imperfect system. But the careful rules of foresnic analysis MUST be followed..

Firearms Analysis in Murder Conviction Rejected


On the third day of a retrial of an October 2008 Virginia murder conviction, forensics supervisors testified that the forensic firearms analysis in the case was incomplete, did not follow procedure, missed the presence of telltale gunpowder particles, and used inappropriate fabric to judge the firing distance.

On the third day of a retrial of an October 2008 Virginia murder conviction, forensics supervisors testified that the forensic firearms analysis in the case was incomplete, did not follow procedure, missed the presence of telltale gunpowder particles, and used inappropriate fabric to judge the firing distance.

The victim's body was exhumed to prove the exact length of her arm, a crucial element in the muzzle-to-wound distance estimated by the original forensics investigators to determine whether the death was murder or suicide.

The conclusions and results stemming from the original forensic tests conducted on the .45 caliber weapon found near the body and on a black tube-top she wore the night of her death could not be duplicated, and the analyst who performed the tests has since been let go for failure to follow procedures on other cases.

Source: Richmond Times-Dispatch

http://www.forensicmag.com/news/firearms-analysis-murder-conviction-rejected

H. Michael's Take:

Here - the excellent work of the criminal defense lawyers defending the accused, their hard work and study of the complex procedures that must be carefully followed before forensic evidence will be admitted at trial -- may save the accused from an unfair conviction... well done. The testing here is called proximity testing.

When you retain your Colorado Criminal Defense Lawyer -- make certain that he or she goes the extra mile and examines, researches and studies every piece of evidence against you.. as was done here.

Proximity testing measures the remants and spread of the stream of heated particles
(Gun Shot Resiue or GSR) that emerge from the muzzle of a weapon that has been fired at a special cloth designed to measure the distance of the muzzle at the time of discharge.

Gunshot residue (GSR) is principally composed of burnt and unburnt particles from the explosive primer, the propellant, as well as components from the bullet, the cartridge case and the firearm used.

In 1971 John Boehm (né Lawless) presented some micrographs of GSR particles found during the examination of bullet entrance holes using a scanning electron microscope. If the scanning electron microscope is equipped with an X-ray microanalysis (electron microprobe), the chemical elements present in such particles, mainly lead, antimony and barium, can be identified.

August 12, 2010

The Next Step in DNA Identification Procedures: Familial DNA


New DNA testing technology may soon be available in the nations crime labs. Crime labs could soon have new technology to help them solve cold cases....known as "familial DNA."

Familial DNA is usd by investigators seeking to find relatives of criminal suspects. Prosecutors want the procedures approved as an investigative tool for police, and defense attorneys say they support the idea as well.

Familial searching

Familial searching is the use of family members' DNA to identify a closely related suspect in jurisdictions where large DNA databases exist, but no exact match has been found. The first successful use of the practice was in a UK case where a man was convicted of manslaughter when he threw a brick stained with his own blood into a moving car.

Police could not get an exact match to the UK's DNA database because the man had no criminal convictions, but police implicated him using a close relative's DNA. The technique was used to catch a Los Angeles serial killer known as the "Grim Sleeper" in 2010.

However, critics have challenged the technology as "deeply antithetical to American values" and likely to lead to excess investigation of racial and ethnic minorities.

H. Michael's Take

DNA evidence is, in the opinion of most criminal defense attorney's, while certainly recognized as a double edged sword, has been used to free the innocent either accused of crimes they have not committed or to obtain the release of those in prison who have been unfairly convicted on the weakest of evidence-identification and circumstantial evidence.

Mitch Morrissey - Denver DA Morrissey makes this point in the following quote 'the good news about partial matches is that if DNA leads police to someone who's innocent, that same DNA should also be able to clear that person just as fast."