Wiggum is one of the Master's failed experiments in trying to awaken psychic powers in humans. Wiggum, while seemingly not as insane as other psykers, is quite clearly depressive. Described as a complete loser, he is wearing a psychic nullifier.
Wiggum is an electrokinetic-dominant psyker. These powers are suppressed when Wiggum is fitted with a psychic nullifier, but smalls sparks of energy still eminate from and over his body.