As a business litigation attorney I find I often need to employ expert witnesses.  Expert witnesses are individuals who have special knowledge in areas not commonly known by others.

If they can provide information useful for the jury to understand an issue the courts generally allow their testimony.  Examples of the use of expert witnesses in business litigation are for opinions on business evaluations, lost profits, the reasonable value of a royalty, and intellectual property values.

The procedure for designating experts is spelled out in the statutes.  Once a demand for an exchange of expert witnesses is made, each side has a time frame to retain an expert.

Rebuttal experts are also allowed and do not have to be designated.  However, rebuttal experts cannot render opinions.  They can only testify that an opposing expert’s foundational fact in forming his or her opinion was incorrect.

The best way to take an expert’s deposition is only ask for his or her opinions and the basis for them.  I do not try to impeach them at the deposition because if you do so you are only showing your hand and your trial strategy.  Wait until trial to show the expert that his or her assumptions relied upon in forming the opinions at the deposition were faulty.  If a foundational assumption is incorrect, the final opinion will also be flawed.