ill-gotten gains - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Benefits obtained in an evil manner or by dishonest means, as in They duped their senile uncle into leaving them a fortune and are now enjoying their ill-gotten gains. [Mid-1800s]