Impulsive-violent offenders are often less capable of controlling their behavior. A cued Go/No-go task was used to test the hypothesis that impulsive-violent behavior reflects a deficit in the ability to inhibit prepotent responses and could be reflected in the measurement of event-related potentials. Results showed that the amplitudes of the N2 component at Fz reflected different degrees of inhibition in impulsive-violent offenders compared with matched controls. The N2 amplitude (No-go minus Go) was significantly lower in the impulsive-violent offenders than in matched controls. The amplitude of N2 increased when effort was required to withhold the Go intention. A smaller N2 amplitude was seen in offenders, suggesting difficulties with inhibition of prepotent behavior.