Ensuring equal access to public education for students with disabilities is one of the primary purposes of the Individuals with Disabilities Education Act (IDEA;). Yet, many schools respond to behavior infractions by suspending students with disabilities, thus removing them from the educational environment, leading legal scholars to suggest that disciplinary exclusion represents de facto denial of educational access (Pauken & Daniel, 2000). Because exclusionary discipline may infringe on students' rights to a free and appropriate public education, it is imperative that researchers and practitioners examine whether such practices are discriminatory. To this end, scholars often first look for descriptive evidence of group-based differences, known as disparate impact, in outcomes, such as out-of-school suspension. Such evidence serves as a precursor for theories about and investigations into disparate treatment (i.e., discriminatory practices) underlying observed outcomes. Despite decades of research into special education disparities, we are still in the initial stages of understanding the disparate impact of disciplinary exclusion on students with disabilities, which is the focus here.Prior researchers indicated that exclusionary discipline is disproportionately applied to students with disabilities relative to students who do not have disabilities. Nationally, approximately 7% of students are suspended (Losen & Gillespie, 2012), but estimates for students with disabilities are above 15% and upward of 44% for students identified under the IDEA category of emotional disturbance (ED; Achilles, McLaughlin, & Croninger, 2007). Furthermore, out-of-school suspension of students with disabilities has increased over time (Krezmien, Leone, & Achilles, 2006;Zhang, Katsiyannis, & Herbst, 2004). Among secondary students with ED, in particular, rates of suspension have risen nearly 50% since the 1980s (Wagner, Newman, & Cameto, 2004). This basic evidence of disparate impact is alarming because suspension is ineffective for reducing inappropriate behavior (Hemphill, Toumbourou, Herrenkohl, McMorris, & Catalano, 2006) and is associated with a variety of negative educational and social outcomes including future disciplinary infractions, repeated suspension, academic failure,