Wiktionary
vb. (context idiomatic usually with ''on'' English) To examine in order to find negative information for public opinion, usually with the purpose of embarrassing or discrediting a person.
Usage examples of "dig up dirt".
The family needed to know what was going on, that Alvin had enemies from the capital who were spending money on a lawyer to come dig up dirt about the boy.
I said I'd keester communists and bash ban-the-bombers, and dig up dirt on that dowager dyke Eleanor Roosevelt.
And if somebody wants to dig up dirt on what a couple of eighteen-yearolds were up to back in seventy-seven, it might make a cute story, but itd be pretty thin soup.
Of course, I might have to dig up dirt about everyone on the committee.
Those lawyers had detectives who could dig up dirt on the Lush and the Whore.
He considers them worthless, and spent half his police career trying to dig up dirt about them.
Reporters had tried before, and failed, to dig up dirt on the man.
How else to describe Hillary's hiring of private eyes to dig up dirt on Bill's enemies and erstwhile paramours?