Exculpation

noun

1. The act of exculpating or of exonerating from a charge of fault or crime; vindication.
2. The act of exculpating from alleged fault or crime; that which exculpates; excuse.
3. The act of exculpating from alleged fault or crime; that which exculpates; excuse.
4. a defense of some offensive behavior or some failure to keep a promise etc.

   "his transparent self-justification was unacceptable"

5. the act of freeing from guilt or blame