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Law 101: Legal Guide for the Forensic Expert

Inadequate Preparation and Ethical Violations

Only sometimes are expert witnesses actually found culpable for preparing fraudulent or false scientific, technical or professional research. Unfortunately, those cases attract a tremendous amount of attention and bring massive disfavor to an otherwise honorable profession.

Horror stories circulating in legal and forensic fields about scientific witnesses who have actually falsified data to support either a prosecution or a defense posture in a criminal case are well known. The use of false DNA, blood, alcohol or chemical substance tests, resulting in wrongful incarceration of accused defendants, stands as the most reprehensible of all forensic witness abuses.

On occasion, experts will tender testimony to the court based on supposed scientific, technical or professional findings and research when they did not, in fact, do the work represented by their report.

Occasionally, the courts are faced with the problem of forged, altered or otherwise falsified documents, data or lab reports that support supposedly expert testimony. In those situations, when exposed, the resulting exclusion of expert testimony seems most appropriate. Sanctions should also be imposed by the courts on both the witnesses and the attorneys who were informed beforehand of the hoax.

Sometimes, an expert witness will recant prior testimony in a similar case because it does not particularly fit facts and circumstances of the present case. Inconsistent or unprofessional testimony is often exposed in the courtroom by aggressive cross-examination. Articulate cross-examination and stringent professional grievance practices may help eliminate such practices from the courts and the dispute resolution process.

Occasionally, expert witnesses display a lack of knowledge or professional competence to render the opinions that are sought. In those circumstances, the likely result is that expert testimony will be admitted (subject to cross-examination) and discounted by the fact finder because it has insufficient weight to be persuasive. Alternatively, the witness may fail to qualify as an expert and be denied the opportunity to testify.

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