Barty Crouch was in charge of the Department of Magical Law Enforcement once. He spent too much time on this career to save his son, Barty Crouch Jr., from becoming a Death Eater.
Barty Crouch appears only in Harry Potter and the Goblet of Fire. He is seen firing Winky the house-elf. We learn at the end that he lead a tragic existence, living out his last year under the Imperius Curse. He is killed by his son.