An expert witness is one of many different witnesses you might use to prove your claim, including eyewitnesses and character witnesses. An expert witness is highly qualified in a particular field, such as medicine or accident reconstruction.
Expert witnesses are very common in personal injury law, especially for medical malpractice and product liability claims. An expert witness can testify in court or at a deposition. Experts also prepare investigation reports that constitute admissible evidence in court or settlement negotiations.
How California Courts Qualify Expert Witnesses
The California Evidence Code specifies the principles of qualifying expert witnesses. The Code does not specify any particular qualifications, only “special knowledge, skill, experience, training, or education.” When one party calls an expert witness, the other party may cross-examine the witness on their qualifications.
The opposing party may cross-examine the expert on both their qualifications and the content of their testimony. The opposing party may cross-examine the expert both in court and at a deposition called during the pre-trial discovery process. Prior to the filing of a lawsuit complaint, however, it can be difficult to compel the opposing party’s expert witness to submit to cross-examination.
The Qualifications of an Expert Witness
To evaluate the qualifications of an expert, a lawyer typically considers the following achievements:
- Academic qualifications: An expert usually, but not always, needs an advanced degree in the subject matter at issue.
- Professional experience: An expert typically possesses many years of professional experience in the relevant subject matter.
- Publications: Publications in respected academic journals typically bolster an expert’s qualifications. Publications in the popular media typically carry less weight.
- Awards issued by the expert’s professional peers.
- Experience testifying, especially experience in undergoing cross-examination;
- Reputation among professional peers.
- Name recognition in the field. General fame, such as the fame enjoyed by celebrities like “Dr. Phil”, typically doesn’t carry as much weight, especially in the eyes of courts.
An expert does not need all these qualifications.
What Is a “Professional Expert Witness”?
Almost all expert witnesses receive pay for their testimony because expert testimony requires labor. A so-called “professional expert witness” derives most or all of their income from testifying in court cases or depositions. Such witnesses are typically retired professionals in the field of their expertise. A retired physician, for example, might work as a professional medical expert witness.
You can be certain that the other side will make sure that the jury knows your expert witness is being paid for their testimony and that they are professional witnesses. This probably won’t matter much, however, for two reasons:
- The use of professional expert witness testimony is routine, especially in certain kinds of cases; and
- The other side might rely on their own professional expert witness.
Many personal injury claims devolve into a “battle of the experts” scenario in which the experts from the respective parties contradict each other.
How Do Parties Use Expert Witnesses?
A party might use an expert witness in the following ways:
- To win a medical malpractice claim by proving that the defendant doctor failed to meet the professional standard of care in (for example) a surgical procedure that harmed a patient.
- To determine whether a particular consumer product contained a design defect that rendered the product unreasonably dangerous.
- To reconstruct a car accident to determine which driver was at fault.
- To estimate your lifetime medical expenses after a catastrophic injury.
- To estimate your future financial losses from an occupational disability that forced you to change professions.
- To interpret physical evidence such as DNA samples.
There are an almost unlimited number of uses for an expert witness.
The Role of the Jury
A jury does not have to accept the testimony of an expert witness. Instead, they weigh the testimony and the other evidence to make their own decision. The judge will issue instructions to the jury on how to use expert testimony. A mistrial might result if the jury fails to follow the court’s instructions. If this happens, you will need a new trial.
Paying for an Expert Witness
Expert witnesses don’t come cheap. Their fees don’t count as “legal fees” (which go to your lawyer) but as “expenses.” When and whether you pay expenses depends on your agreement with your lawyer. Some lawyers will pay your fees upfront and bill you for reimbursement if and only if they win your case. Other lawyers will bill you for these expenses at the time they arise, and you are liable for them whether you win or lose.
An Experienced Personal Injury Lawyer Can Help You Locate an Expert Witness
Almost any experienced personal injury lawyer maintains contact with expert witnesses. A personal injury lawyer will also have experience using individual expert witnesses in previous cases. If your case is complex enough to need an expert witness, you probably need to hire an attorney anyway.