Stigma about mental illness is often identified as one of the most prominent obstacles to seeking mental health services. This seems to be particularly true among first responders. Unfortunately, the research regarding stigma in first responders is lacking. This may be due, in part, to the absence of appropriate measurement tools to allow such research. Stuart’s Police Officer Stigma Scale (POSS) has recently been developed to address this issue, but its psychometric properties have gone largely untested. Therefore, this study sought to identify the underlying factor structure and internal consistency of the POSS. This paper used a sample of one hundred and thirty-five first responders. This paper used a sample of one hundred and thirty-five first responders. Sixty participants were police officers, forty-eight were firefighters/EMTs, three were dispatchers, and twenty-four did not complete some portion of the scale/training and were omitted. Using factor analysis with an orthogonal rotation on Stuart’s eleven-item POSS, the participant’s results revealed two main components. Component one is “maltreatment of colleagues with a mental disorder,” and component two is “fear of disclosing a mental disorder.” Findings from this research are similar to the results of previous studies with components such as unwillingness to disclose a mental health condition, fear of how the public will treat an individual with a mental disorder, and anger towards those who decide to seek treatment or get diagnosed with a mental illness. These findings imply that Stuart’s POSS is reliable but needs to include two components rather than one. With the two main components, further research can now be conducted to understand why and ultimately mitigate maltreatment or stigma against first responders with a mental health condition.