One who perpetrates; especially, one who commits an offence or crime.(noun)
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Use "perpetrator" in a sentence
"In both cases the perpetrator is a pre-defined Bad Guy who deserves everything he gets."
"Sotomayor says that this experience taught her how crime “destroys families” even years after the perpetrator is locked up."
"As tough as this procedure can be on you both physically and emotionally, you go through it because you know that gathering evidence of this crime will insure that the perpetrator is not only caught, but also incarcerated so that he can never hurt anyone again."