The purpose of this paper is to explore a subject on trial and outlaw ethics in William Faulkner’s Light in August in terms of Julia Kristeva’s theory of the subject. In Light in August Faulkner depicts the ultimate abomination of otherness, which shows the intersection of gender and race within Southern white myths. According to Kristeva the subject and society have been founded on the abject’s separation. Joe Christmas’s identity which characterizes this mechanism of abjection as a subject on trial illuminates the paradoxical state of otherness within his subjectivity against gender and race. His extreme exclusion of abject, heterogeneity but himself, draws ruin upon himself in the end. Faulkner suggests Lena Grove, a heavily pregnant woman, as an outlaw ethics for a subject on trial. The final aim of the maternal theory Kristeva emphasizes is the maternal love which is the attitude to alterity. That is, mother loves the other in herself and then she can embrace the return of the repressed other. In Conclusion, Joe Christmas’ tragedy comes from the rejection of his object. Therefore, My study suggests he should have developed his identity constantly by emptying and attacking inner conflicts as he met the abject.