Expert opinion

Good habits start early: Identifying and managing potential bias in forensic evaluations as an early career forensic psychologist

What can early career forensic psychologists do to avoid bias in their evaluations?

By Marc A. Martinez, PhD

The American Psychology Association's ethical standards (American Psychological Association, 2010) and specialty guidelines for forensic psychology (American Psychological Association, 2013) note the importance of maintaining objectivity in the practice of forensic psychology. Bias, however, challenges a professional's ability to adhere to these standards and guidelines, often beyond awareness. The influence of bias has been shown to affect professionals regardless of years of experience (Grove, Zald, Lebow, Snitz, & Nelson, 2000; Sladeczek, Dumont, Martel, & Karagiannakis, 2006). Early career forensic psychologists (i.e., those within seven years of receiving their doctoral degree), however, have the advantage of forming valuable habits from the outset that will enable them to identify and manage bias effectively throughout their career (Green & Hawley, 2009; Smith et al., 2012).

At each stage of an evaluation, forensic psychologists must navigate a complex process of seeking relevant information while maintaining an objective outlook and remaining mindful of potential bias that may undermine or limit their efforts. The influence of bias on the opinions of mental health care and other professionals has been well-documented (Borum, Otto, & Golding, 1993; Croskerry, 2002; Dawes, 1994; Faust, 2012; Hilton, Harris, & Rice, 2006). Authors examining the role of bias agree that awareness is a crucial first step toward mitigating its potential influence. Unfortunately, research has shown that awareness of bias alone has little or no corrective effect (Larrick, 2004; Nickerson, 2004). For this reason, it is imperative that forensic psychologists move beyond mere awareness and become committed to corrective measures on a routine basis. A selection of some of the most commonly cited biases identified in forensic psychological literature is provided in Table 1.

Table 1.

Anchoring or primacy bias

Information received at the outset of a case may lead to initial ideas and formulations that are difficult to abandon.

Confirmatory bias

Focusing on evidence that supports rather than disconfirms a hypothesis.

Underutilization of base rates

Failing to consider base rates when making judgments and predictions may result in overprediction or underprediction of the outcome of interest.

Inaccuracy from overreliance on memory

An overreliance on memory in forensic evaluations has the likelihood to result in a decrease in accurate information recall and increase in judgment bias.

Diagnosis momentum

Assigning a particular diagnosis without adequate evidence, which gathers momentum over time to the point that it may appear accurate.

Allegiance effect

Formation of opinions in favor of the retaining party rather than on an objective assessment of available evidence.

Fundamental attribution error

Attributing more weight to dispositional qualities rather than situational circumstances when considering the reasons for someone's behavior.


Overconfidence may lead to insufficient data collection and synthesizing of information prematurely.

Because awareness alone does little to avoid bias, several general strategies have been suggested in practice literature toprevent or mitigate the effect of bias (e.g., Borum, Otto, & Golding, 1993; Croskerry, 2002; Grove, Zald, Lebow, Snitz, & Nelson, 2000; Hilton, Harris, & Rice, 2006; Rogers & Shuman, 2000). Examples of corrective measures for the sources of bias listed in Table 1are provided below in Table 2.

Table 2.

Anchoring or primacy bias



-Ask the retaining attorney or referral source to provide not only facts that support their position, but also the facts that the opposing side will likely argue.

-Utilize systematic data gathering (e.g., structured interviews).

-Avoid lengthy pre-evaluation interviews with attorneys.

-Engage in rigorous consideration of alternative hypotheses.

Confirmatory bias

-Generate a list of possible hypotheses near the outset of a case relevant to the legal question that are competing and seek out confirming and disconfirming evidence.

-Modify initial impressions based on disconfirming information.

Underutilization of base rates


-Seek out reliable estimates of conditions or outcomes relevant in a particular case.

-Absent specific base rate information, consider base rates of similar conditions or outcomes in other similar populations.

-Appreciate that infrequently occurring conditions or outcomes are by their very nature difficult to predict but often the issues that forensic psychologist are called to address.

Inaccuracy from overreliance on memory

-Record information immediately throughout evaluation process or as soon as possible.

-Consider utilizing video or audiotaping in addition to note taking.

-Utilize an organization system for documenting available information (e.g., process for indexing large amounts of records for later referencing).

Diagnosis momentum

-Avoid accepting a previous diagnosis as accurate without independently considering confirming and disconfirming evidence.

-Withhold assigning a diagnosis in the event there is insufficient information.

-Consider listing a previous diagnosis but indicate lack of information to support presently.

Allegiance effect

-Form a list of potential hypotheses early in the evaluation process.

-Diversifying a forensic practice may reduce pressure to satisfy the referral source due to interest in future referrals.

-Strive to utilize objective and systematic methods for evaluation and forming conclusions.

-Clearly state at the outset of a professional relationship thatconclusions are based on the data available and may not support the retaining party's position.

Fundamental attribution error

While considering hypotheses, confirming and disconfirming evidence should also include situational variables that may explain a particular condition or outcome.


-Identify competing hypotheses and consider evidence that supports and disconfirms each.

-Consider the differences in validity of the information being considered and its relationship to a valid opinion or prediction.

-If systematic feedback is available after forming conclusions, it may assist in forming knowledge of predictive validity.

-Acknowledge areas of limitation.

Given the serious consequences that are often at stake in forensic psychological evaluations, evaluators must vigilantly protect their objectivity and strive to adhere to ethical standards and practice guidelines. Regardless of a forensic psychologist's career stage, all are susceptible to the influence of bias. Because of their recent transition into practice, early career forensic psychologists are in an excellent position to implement skills necessary to identify and manage potential sources of bias at the outset. Use of tools to combat bias, like those identified above, will benefit forensic psychologists throughout their career.


American Psychological Association. (2010). Ethical standards and code of conduct (2002, Amended June 1, 2010). Retrieved September 20, 2011, from

American Psychological Association. (2013). Specialty guidelines for forensic psychology. American Psychologist, 68, 7-19.

Borum, R., Otto, R., & Golding, S. (1993). Improving clinical judgment and decision making in forensic evaluation. The Journal of Psychiatry & Law, 21, 35-76.

Croskerry, P. (2002). Achieving Quality in Clinical Decision Making: Cognitive Strategies and Detection of Bias. Academic Emergency Medicine Journal, 9, 1184-1204.

Dawes, R. M. (1994). House of cards. New York: The Free Press.

Faust, D. (2012). Coping with psychiatric and psychological testimony: Sixth edition. New York: Oxford University Press.

Green, A. G., & Hawley, G. C. (2009). Early career psychologists: Understanding, engaging, and mentoring tomorrow's leaders. Professional Psychology: Research and Practice, 40, 206-212.

Grove, W. M., Zald, D. H., Lebow, B. S., Snitz, B. E., & Nelson, C. (2000). Clinical vs. mechanical prediction: A meta-analysis. Psychological Assessment, 12, 19-30.

Hilton, N. Z., Harris, G. T., & Rice, M. E. (2006). Sixty-six years of research on the clinical versus actuarial prediction of violence. The Counseling Psychologist, 34, 400-409.

Larrick, R. P. (2004). Debiasing. In D. J. Koehler & N. Harvey (Eds.), Blackwell handbook of judgment and decision making (pp. 316-337). Malden, MA: Blackwell Publishing.

Nickerson, R. S. (2004). Cognition and chance: The psychology of probabilistic reasoning. Mahwah, NJ: Lawrence Erlbaum Associates.

Rogers, R., & Shuman, D. W. (2000). Conducting Insanity Evaluations ( 2 nd ed. ) . New York: The Guilford Press.

Sladeczek, I. E., Dumont, F., Martel, C. A. & Karagiannakis, A. (2006). Making sense of client data: Clinical experience and confirmation revisited. American Journal of Psychotherapy, 60, 375-391.

Smith, N. G., Keller, B. K., Mollen, D., Bledsoe, M. L., Buhin, L., Edwards, L. M., et al. (2012). Voices of early career psychologists in Division 17, the Society of Counseling Psychology. Counseling Psychologist, 40, 704-825.