The Rorschach is a projective test frequently used in the forensic ambit for the information it can give in both the cognitive and affective areas. The purpose of our work is to identify the traits recurring in perpetrators of the “crime of impetus” through the examination of the psychometric indices of the Rorschach.

15 male subjects between 22 and 60 years (mean age = 43.2 ± 10.96 years) authors of murders, without previous psychiatric disorders, were tested; the control group was represented by 15 subjects without history of crimes. All protocols were collected and signed through the method “Scuola Romana Rorschach” and the scores of psychometric indices were compared between and within groups by Student's t-test.

From the cognitive point of view there were no significant differences concerning the sense of reality between the murderers and control samples (R+% = 75,87 vs 70,73; p = 0,241. F+% = 75,47 vs 76,93; p = 0,653), but the number of responses was lower than average (16,67 vs 25,27; p < 0,0001). The most significant differences in the murderers appeared in the G/M Index (G = 7,73vs9,35; p < 0,005. M = 2,37vs 1,00; p < 0,0001) and in the Impulsivity Index (0,96 vs 0,33; p=0,0002).

According to the most recent literature the Rorschach indices showed in the perpetrators of the “crime of impetus” the absence of mental disorders; however, the disproportion of the Index G/M and Impulsivity Index may indicate a “vulnerable anthropology” as a risk factor for impulsive crime in the presence of emotional stress.