The Triarchic Measure of Psychopathy (TriPM) was developed to assess manifest expressions of biobehavioural liabilities relevant to psychopathy and other forms of mental illness. Psychometric findings have been examined for a number of international translations of the TriPM, but further work is needed to evaluate its cross-cultural applicability and its properties in clinical versus nonclinical samples. The present study sought to evaluate the reliability and criterion-related validity and characterize the internal factor structure of the European Portuguese version of the TriPM in a large community sample (N = 1,833), and examine its ability to differentiate between community and prisoner (N = 240) samples. Reliability and criterion-related validity analysis supported the TriPM as an effective measure of psychopathic traits. Internal structure was characterized using exploratory structural equation modeling to specify bifactor models for the TriPM's three subscales and for the inventory as a whole; the model for each subscale included a general factor and a variable number of specific factors as determined by parallel analysis. These modeling analyses demonstrated unidimensionality for each TriPM subscale, and provided support for the triarchic structure of the TriPM as a whole. Additionally, Receiver Operating Characteristics analysis showed that the disinhibition score, as assessed by the TriPM, is the most sensitive for differentiating between prisoner and community samples. Our results are in line with other reports regarding the psychometric properties of the TriPM and provide further evidence for the construct validity of the TriPM. (PsycINFO Database Record (c) 2020 APA, all rights reserved).