Despite federal regulations around making determinations about special education eligibility, the system is vulnerable to biases influencing decision making. The present study investigated the impact of bias on special education eligibility decision making. The research questions ascertained whether manipulation of a single piece of information in case vignettes about a student being considered for special education eligibility could expose the impact of confirmation bias, groupthink, and race on decision making. Surveys were distributed to school psychologists in Massachusetts via the online platform, Qualtrics. Each participant was randomized to a group in which they received vignettes about confirmation bias, groupthink, and race from varying conditions (Positive, Negative, and Neutral). A Chi-Square analysis was completed using the Statistical Package for the Social Sciences (SPSS) online software to determine if bias was identified across biases and conditions. A Chi-Square Test of Homogeneity revealed that the Positive Confirmation Bias vignette was the only condition statistically significantly different from all other conditions. Limitations of this study included a lack of random sampling and only recruiting school psychologists in Massachusetts. Implications of these results suggest limiting the amount of information multidisciplinary team members know when making a special education eligibility decision to reduce confirmation bias and incorporation of consistent methods to increase internal consistency across special education eligibility decisions. Future study directions include assessing other biases through vignettes that may impact special education eligibility processes. In addition, conducting this study within a group setting to better simulate special education decision making teams is of great importance. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]