Expert testimony is typically offered following an evaluation of a plaintiff or defendant in a case. Expert witnesses are to remain impartial regardless of who hired them. Most mental health experts report that they are able to remain unbiased in their work (Commons, Miller, & Guthiel, 2004). Recent research, however, indicates mental health experts are often biased toward the side that hired them (Murrie & Boccaccini, 2015). Experts are aware of the threat of bias and readily identify bias in their colleagues, yet relatively few experts believe bias has influenced their work (Neal, 2016; Murrie, 2017).   

Bias is often unconscious. It is very difficult to recognize one’s own bias even while  identifying bias in others, a phenomenon known as the bias blind spot (Pronin & Kugler, 2007). Many mental health professionals report avoiding bias by remaining aware of its possibility or internally reflecting on it, what is often called introspection. Introspection does not appear to be an effective method of reducing bias (Zapf & Dror, 2017;  Neal, Lienert, Denne & Singh, 2022). 

There are strategies that can effectively reduce potential bias, but not all experts use them. They can be difficult and time-consuming to implement and may be perceived as overly mechanical, inapplicable based on idiosyncratic individual characteristics, or undermining of clinical judgment.  Some experts remain unconvinced of the risk of bias to their own work and unaware of the importance of implementing effective bias prevention strategies for every case. In such cases, an expert’s unconscious bias can often be exposed with vigorous cross examination.