Can DNA Evidence Be Used Against Me in Court?

Over the last decade several TV shows like CSI, NCIS, and Law and Order have “educated” us on the use of DNA evidence in criminal cases, and, primarily, in sex crime cases.  DNA evidence is, in fact, being used throughout the country both to prosecute and defend countless individuals charged with various crimes, but that does not mean it is infallible.

In 2013, the United States Supreme Court ruled for the first time that criminal suspects can be subjected to a police DNA test after their arrest and before either a trial or conviction.  In their decision, the Supreme Court held that “when officers make an arrest supported by probable cause to hold for a serious offense and bring the suspect to the station to be detained in custody, taking and analyzing a cheek swab of the arrestee’s DNA is, like fingerprinting and photographing, a legitimate police booking procedure that is reasonable under the Fourth Amendment,” of the United States Constitution.

If the State has the right to analyze your DNA, the question becomes, is that DNA evidence admissible against you, or for your defense, in Court?  The answer is generally, but not always, yes.  If the investigators properly collected and handled the DNA evidence and the forensics scientists employed the proper and acceptable analytical methods, the evidence is, again generally, accurate and, thus, admissible in a trial.

However, DNA evidence is not above challenge.  While often accurate, errors by the individuals handling, maintaining, or collecting the DNA can contaminate the DNA sample and making it inaccurate and inadmissible at trial.  Further, there are countless examples of labs contaminating samples, failing to follow chain of custody procedures, and using unreliable testing methods that can also prevent the use of DNA evidence at trial.  One New York Judge recently tossed out several DNA samples for the lab’s failure to use proper testing procedures.

For example, the now famous Amanda Knox case was decided, in part, based on the poor handling of DNA evidence obtained by the prosecutors.  In her case, the prosecution relied heavily on DNA evidence found on a knife and bra clasp in order to convict Ms. Knox.  However, a review of the authorities’ collection and handling of this evidence brought into question its validity.  The authorities in Ms. Knox’s case allowed the DNA evidence to be stored in regular plastic bags where moisture can build up and degrade the samples.  They also failed to properly test the knife at issue and confused potato starch for bleach, calling into question their testing methods and abilities.  The Knox case demonstrates just some of the issues that can come into play with DNA evidence and its admissibility.

As you can see, DNA evidence is not always accurate, nor is is always admissible.  If you or someone you know has been charged or convicted of a crime and DNA evidence is an issue, contact one of the experienced criminal law attorneys at Hipskind & McAninch for a FREE CONSULTATION.  Contact us at: 618-641-9189 (IL) | 314-312-2930 (MO) |

Authored by: Brady McAninch