Forensic, General & Medical
Expert Witnesses

Disqualifying an Expert Witness Due to Bias

     By HG.org

Expert witnesses are hired to provide details, remove confusion or connect certain evidence and persons to the incident where someone has been wronged or injured. However, sometimes these professionals are disqualified because they have bias with the other party, a conflict of interest or a bias with the case itself.
When there is the possibility that an expert witness is biased, his or her testimony and evidence connecting certain events or persons together is given less weight and there is less confidence in the professional to begin with. It is imperative that the bias is cleared from the expert before moving on and permitting him or her from participating further. This could lead to the expert being disqualified, but his or her opinion may still remain admissible based on what the judge has determined before the professional is removed from the case. The evidence, however, will still need evaluation and consideration.

When there is the possibility that an expert is biased in a case, his or her evidence, testimony and opinion are all subject to examination so that each may be determined sufficiently clear for admitting into the case in the courtroom. If the expert is not qualified to give testimony, his or her opinions may still be used based on other factors, but opinion evidence could be inadmissible if the professional is not qualified based on bias. Through the Supreme Court, it has been established that being qualified involves independence, objective and impartial elements for the expert witness.

What is Bias with an Expert Witness?

When a courtroom has accepted an expert witness, the expectation is that he or she will give unbiased and objected opinions, testimony and evidence for the case. However, some are not unaffected by the incident, scene or injuries. When these factors change what the expert thinks or feels about the claim, he or she may be compromised. His or her attitude is altered to suit the needs of the litigation instead of maintaining objectivity and keeping emotion and thought out of the testimony. While the lawyer appears to have a side, he or she may only be protecting the rights of the client. When the expert witness does the same, he or she is considered biased.

If the evidence or opinions are not helpful or persuasive to the judge or jury, they are given less weight than usual. However, when the expert has become swayed by evidence, injury or the defending party, he or she may be disqualified in the case. It is important for the judge to determine if this bias does exist and the professional is not just exerting his or her independence in the case. If there is a pre-existing relationship with the client, defendant or lawyer and the expert witness, this could create a biased attitude. However, other factors are often considered of greater importance such as a leaning in testimony or methods used.

Disqualifying the Expert Witness

It is when the judge has been able to determine that the expert witness has leaned to one way in his or her testimony, opinion or evidence that he or she may consider the professional biased. He or she may use other factors to help in deciding to disqualify the expert, but because this is a serious situation, the judge will ensure the expert is only removed based on factual evidence. If the expert witness is unable to comply with sworn duties, he or she should not be able to give admissible testimony. Then, he or she is considered biased and disqualified in the case.

Another form of bias is observed through adversarial bias when the expert is working for the lawyer to help the client by persuading the courtroom to one way of thinking. This is not usually considered grounds for disqualification. However, conscious bias may be one of these elements. These persons may provide testimony based on what they perceive. The weight of this testimony is less than what is given to scientists and those with factual information. This could lead to a Daubert challenge against relevance and reliability in methods, evidence and opinions.

Expert Witness Bias Disqualification

When the judge has determined that the expert is swayed by evidence, injury or the client, he or she may be disqualified from providing evidence, testimony or a report on the matter. If the methods used are subject to a Daubert challenge, this could lead to disqualification as well. When bias is observed, loss of credibility is often next.

Copyright HG.org


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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