How Important is Science in the Courtroom?

Science has been a part of courtroom drama for decades, and while it has been useful in some regards, it has also led to some wrongful convictions. If you are facing charges that are based largely on scientific analysis, there are some facts that a good defense attorney should know.

Bite Mark Analysis

The President’s Council of Advisors on Science and Technology (PCAST) has found that forensic conclusions related to bite mark analysis simply do not meet scientific standards for legitimacy.  Since this type of unreliable analysis has been used fairly often in front of criminal juries, it bears some scrutiny. While attorneys like to dangle so-called expert witnesses in front of juries to stock up their cases, the limits of the technology are rarely presented. In fact, juries deserve to know the rates of error and the potential pitfalls of relying on bite-mark analysis. The questions around this science are so pervasive, in fact, that FBI examiners are no longer permitted to make claims that such analysis provides reasonable certainty in determined outcomes.

Hair Analysis

For more pseudoscience, look to The Guardian’s report of improper testimony related to forensic analysis of hair.  When matching hair samples, it turns out that because certain characteristics of hair are so common, it is unlikely that accurate matches can be found. One expert concludes that this type of microscopic examination is effectively useless when it comes to identifying someone, although it might be useful to exclude a suspect.


Surprisingly, the accuracy of the science behind fingerprint identifications has really never been tested. One problem lies in the training standards that examiners have, which vary widely.  Believe it or not, the majority of fingerprint examiners have not passed certification tests.  Hence, the depth of knowledge any given “expert” has could be called into question. Beyond problems with the examiners themselves, (who are trained to say that the results of their examination provide absolute certainty), there are serious questions about the science itself.  Many courts throughout the country have excluded the use of fingerprint evidence altogether.

Handwriting Analysis

Handwriting analysis is problematic in a courtroom for a number of reasons, not the least of which is the fact that it is largely subjective. Although training is becoming more standardized with time, this analysis is viewed as shaky, at best. Problems with this practice include:

  • No error rate in the assessment procedure has been determined;
  • Comparisons of upper- and lowercase letters cannot be relied on;
  • An individual’s handwriting may differ greatly based on a number of factors, including illness, the type of writing (applications and forms vs. letters, for example) and even state of mind;
  • Exemplars with which to compare a writing sample may be difficult to locate.

The Right to a Strong Defense

Every American is entitled to a vigorous defense in a court of law. At the Robert Foley Law Firm, we pride ourselves on our ability to challenge questionable evidence in our efforts to provide clients with the best defense possible. Contact us in Fort Myers or Punta Gorda for a free, confidential consultation.