Motivational interviewing (MI) is often incorporated into screening, brief intervention, and referral to treatment (SBIRT) interventions in critical care settings to address alcohol and other drug use. However, cognitive status has been linked to differential response to MI sessions in emergency department (ED) settings. The current study examined one possible explanation for this differential response: whether higher versus lower mental status impacts patient response to clinician statements during MI sessions conducted in an ED. Participants were 126 patients receiving an MI-based single-session alcohol brief intervention, and 13 therapists who provided treatment. Participants completed a mental status exam (MSE) as part of the screening process. Intervention sessions were audio-taped, and transcribed and coded using the Motivational Interviewing Skills Code (MISC 2.0; Miller, Moyers, Ernst, & Amrhein, 2003). The MISC 2.0 coded therapist behaviors that are related to the use of motivational interviewing, and patient language reflecting movement toward (change talk) or away from (sustain talk) changing personal alcohol use. Overall, patients responded in a similar manner to therapist MI behaviors regardless of high versus low level of mental functioning at the time of the intervention. Group differences emerged on patient response to only three specific therapist skills: giving information, open questions, and complex reflection. Thus, the differential effects of SBIRT in critical care settings do not appear to be a result of differences in the therapist and patient communication process.