Psychologists performing forensic evaluations are usually urged to avoid multiple relationships such as that of being both a therapist and a forensic evaluator, on the same case, for several reasons. First, the methodology in each kind of relationship is different. The therapist works within the framework of a treatment alliance, trying to help the patient or client to deal with various difficulties as the client sees them. As such, the therapist depends on the client as the source of information, and, in fact, contacting collateral sources or administering testing to explore level of motivation could interfere with the therapeutic relationship, especially in psychodynamic, humanistic, and other types of treatments. In contrast, a forensic evaluation should be atheoretical, objective, and neutral, and rely on the integration of multiple sources of data, which of course, therapy does not. Even if a therapist is asked by a client or patient to testify on his or her behalf in a court proceeding, in many cases, it may be wisest to avoid doing so, since questions could come up on cross-examination that could significantly interfere with the therapeutic relationship or even be harmful to the client (Eisner, 2010; Reid, 1998). For instance, a question about whether or not there was an assessment for malingering posed to a therapist who is testifying at his or her client’s request would probably not have a definitive answer, since such an assessment may be inconsistent with the supportive nature of therapy. The therapist would need to answer based only on clinical data since there was no objective, scientific test administered to determine malingering. Thus, the therapist cannot really be sure about whether or not the client is exaggerating or even lying. This could wreak havoc with future therapeutic contact.
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