Case files can show how aggressors use different explanations to reduce the seriousness of their crime. We aimed to identify and categorize a 2016 Brazilian case file from a perpetrator of femicide, based on moral disengagement theory. Content analysis yielded 47 verbalized excerpts, with 70 disengagement occurrences. The most frequently used mechanisms throughout the aggressor's speeches consisted of moral justification and blaming the victim herself. Results indicated that he reduced the seriousness of the femicide and sought reduction of the consequences. We discuss how speeches in criminal cases can serve as a secondary source for producing data on violence.