In What is a finance expert witness?, wiseGeek writes:
In the majority of cases, the potential finance expert witness will be interviewed and asked to give his or her credentials. He or she will also be questioned by the opposing attorney, and his or her demeanor while answering questions will be studied. The person hired should be believable and likable to avoid turning off the jury. He or she should be good at handling pressure during cross examination, and giving answers to complicated questions in terms that jurors will understand.
Payment is generally offered to the finance expert witness for each day he or she is involved with the case. Aside from the actual trial, the witness will often be asked to review files and conduct studies involving financial records in questions. After everything has been studied, he or she will have to give an expert opinion on the findings. The opinion should not be in conflict with the attorney’s case, otherwise another witness may be hired.
Read more: wisegeek.com.