An article in the December 2004 issue of Psychiatric Times discusses a movement to curtail the "traveling expert''--
The current effort to hold expert testimony by physicians as constituting the practice of medicine is another attempt to curtail the "traveling expert." In recent years, ostensibly to improve the quality of expert testimony, a number of states have required licensure in the jurisdiction of the forensic examination or testimony (Reid, 2000).
Tennessee legislation (Tennessee Code Annotated, undated), for example, states:
No person in a health care profession requiring licensure under the laws of this state shall be competent to testify in any court of law to establish the facts required to be established [in a malpractice action] unless the person was licensed to practice in the state or a contiguous bordering state a profession or specialty which would make the person's expert testimony relevant to the issues in the case.
In 1998, the AMA adopted a policy that expert witness testimony by physicians be considered the practice of medicine subject to peer review.
The article, titled "Discrediting the Expert Witness on Account of Bias," by Ralph Slovenko, J.D., Ph.D., also contains a good discussion of some of the policy concerns underlying the rules that determine the parameters of expert cross-examination.