Getting Expert Witness Testimony Admitted in Criminal Cases

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Experts witnesses are often indispensable in criminal cases because they provide services that no one else can such as explaining complicated matters and confusing details. New evidence is discovered, guilt is easier to observe and a reconstruction of the incident is possible using an expert witness.

Experts are used in criminal cases for a variety of reasons. The most notable utilization is for fingerprint matching, DNA evidence corroboration and identification of forensic details. Violent crimes may require the need of additional professionals as part of a case. Psychologists, criminologists and similar professionals are hired to explain behavior and the scene. Judges and jury panels are often confused when there are multiple facets of an incident. Befuddlement extends to problems where more than a single perpetrator is the reason injury happened. Expert knowledge applied to these circumstances unravels the confusion. This may permit the professional to single out the guilty party.

Obligations of the Expert in Criminal Trials

Part of trial strategy is using the expert appropriately. This requires attention to detail, knowing what methods are common in expert testimony and scientific technique. The lawyer may also need to adjust these circumstances based on federal versus state trials. Some experts should be local and others may need additional education or skills to penetrate the deluge of details and evidence. What testimony applies depends on what type of proceeding is taking place. Gauging the jury panel is also crucial to keeping the best fit expert giving details and statements. This is often beneficial, and the chances of success increase.

Some cases require the expert to create a report containing numerous details. His or her opinion based on evidence, testimony and processes completed is within the document to include any visual aids. Sometimes the conclusion will have the testimony listed. To ensure this is admissible, the judge and opposing counsel has the right to review the details. Credentials, reliability and relevance to the subject matter of the case must all pass their inspection. Exhibits to use in the courtroom and qualifications are assessed. If the expert fails any of these examinations, he or she is disqualified as an expert. Testimony is inadmissible.

Criminal Processes for the Expert

The Federal Rules of Criminal Procedure do not require a report before testifying in the courtroom. However, similar to this procedure, the expert must supply a written report that contains testimony. This should include his or her opinions, why he or she has these opinions and qualifications. Scientific and medical reports are usually necessary. However, other documents may be missing from these summaries in criminal proceedings. The expert is freer to conduct his or her investigation or examination into the incident without additional interference. This permits him or her to complete a detailed analysis.

Admissible Testimony and Daubert Factors

Once the expert has passed inspection by the lawyer, he or she must submit to examination by the judge and opposing counsel. The other lawyer will attempt to confuse, disqualify or subject the expert to various types of questions to cause his or her testimony to become inadmissible. Many of the aspects of this procedure involve passing a possible Daubert challenge. This requires the testimony having relevance to the case subject matter, reliable scientific methods and helping the courtroom understand the evidence or incident. If any of these are lacking, the expertís testimony is often inadmissible. He or she may remain as a consultant, but he or she is no longer an expert.

Testimony Passing the Test

Succeeding the Federal Rules of Evidence is necessary and required. The expertís testimony and methods must contain sufficient facts and information. Reliable principles and processes present in examination become relied upon. Most judges use Daubertís factors over the previous Frye factors. However, some experts have additional hoops to jump based on the case and the judge presiding. For criminal cases, the expert must exhibit exceptional qualities and be above reproach. His or her qualifications must succeed challenge and credentials need him or her to have enough experience to remain in the courtroom. Reliability in methods and analysis of evidence becomes critical.

For experts to remain qualified for a criminal case, their testimony cannot contain errors or rely upon eyewitness identification. Other factors such as fingerprint and skin or hair matches may not qualify. Greater care is necessary for these cases, and if the client is the defendant, the lawyer must ensure the expertís processes are unquestionable.


Disclaimer: While every effort has been made to ensure the accuracy of this publication, it is not intended to provide legal advice as individual situations will differ and should be discussed with an expert and/or lawyer.

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