In Preparing and Presenting Expert Testimony, traffic engineer and accident reconstruction expert witness Lawrence Levine writes:
An old and established rule of thumb for attorneys is that the best prepared attorney wins and a good attorney never asks a question for which he does not already know the answer. It can be devastating to the expert’s reputation and to the lawyer’s case, should a topic be undiscovered prior to submission of expert opinions. It can also be devastating to a case for the expert to have a pre-formulated opinion; in other words, for the expert to start at the end (with his opinion), and then work backwards to uncover “how the accident must have happened.” This is faulty thinking. It is crucial to always approach a case with an open mind. Start with all the facts, including depositions and witness statements; see the site and allow the case to build itself naturally.
Normally expert opinions are required to be submitted and exchanged at least 30 days before trial, although this may vary. The submission is either in the form of an affidavit signed by the lawyer, an affidavit of opinions signed by the expert, or an Expert Witness Response signed by the lawyer. Never allow an attorney to prepare and submit an Expert Witness Response without a thorough review. It used to be the case that expert affidavits were the norm and the expert had to sign off on what was being said or prepare it themselves. This is no longer the case. Attorneys have been known to prepare Expert Witness Responses for cases in which they do not even have an expert – hoping to settle the case. Be on guard that this does not happen and report it, if it occurs, to the local Bar Association. On the whole, attorneys are very honest and, as officers of the court, do not engage in unsavory behavior such as this.