Expert witness depositions are part of the discovery stage of litigation, but they deserve special attention due to their high cost and particular prominence in California trust and estate litigation. While the discovery process ends with a “discovery cut-off” 30 days before trial, the expert discovery cut-off extends to 15 days before trial.
Under California Evidence Code Section 801(a), an expert witness may testify in the form of an opinion if the opinion is “related to a subject that is sufficiently beyond common experience that the opinion of an expert would assist the trier of fact.” The “trier of fact” means the judge in a “bench trial” (which means a case decided by a judge rather than a jury, as is the case in most will and trust contests and other probate proceedings) or the jury in a case decided by a jury, such as an elder abuse case.
This means that expert witnesses are allowed to offer their opinions on matters that are outside “common experience” if it would assist the judge or jury. California attorneys and judges seem to be particularly fond of expert testimony; according to one study:
California courts probably rely on expert testimony to a greater extent than any other jurisdiction. In a study supported by the Rand Corporation, researchers found that 86 percent of the civil trials conducted in California Superior Courts involved expert testimony. On average, there were 3.3experts per trial. (Edward J. Imwinkelried and David L. Faigman, Evidence Code Section 802: The Neglected Key to Rationalizing the California Law of Expert Testimony, 42 Loy. L.A. L. Rev. 427 (2009). Available at: https://digitalcommons.lmu.edu/llr/vol42/iss2/3/.
This is certainly true in most will and trust contests, elder abuse, and other trust and estate litigation cases, where the most common experts are: neuropsychologists, psychiatrists, or neurologists; forensic accountants; and forensic document examiners (otherwise known as handwriting experts).
Medical doctors (typically neurologists or psychiatrists) or neuropsychologists are often called upon to testify about the mental capacity of the person who created the will or trust at issue in a will or trust contest. They will also often testify about whether the person was vulnerable to undue influence. In most cases these doctors never examine the person about whom they are opining, instead basing their opinions on medical records and testimony of family and friends.
When money has gone missing in an elder abuse case, or when a trustee is accused of converting trust funds for his personal use, forensic accountants typically analyze financial records and testify about where the money went or how it was spent.
Because forged or altered wills, trusts, deeds, or powers of attorney figure prominently in elder abuse cases and will and trust contests, forensic document examiners are often necessary to testify about the authenticity of signatures or documents.
It is not unusual for experts to charge $500-$600 or more per hour and $5000 per day for court testimony. (A San Francisco neuropsychiatrist we have retained in cases in Contra Costa, Alameda, and Santa Clara Counties charges $750 per hour for depositions and $5000 for a full day of trial testimony.) Because of this enormous expense, expert witness depositions usually occur at the end of the discovery stage, when mediation has failed and settlement discussions are exhausted.