AP Explains: How do politicians collect opposition research?

FILE- In this Sept. 26, 2016, file photo, Democratic presidential nominee Hillary Clinton and Republican presidential nominee Donald Trump appear on a monitor during the presidential debate at Hofstra University in Hempstead, N.Y. Opposition research is a typically inside-the-Beltway term that has burst onto the public stage with the disclosure that President Donald Trump's eldest son was receptive to an offer from a "Russian government attorney" for dirt on Clinton during the 2016 presidential campaign. (AP Photo/Mary Altaffer, File) FILE- In this Sept. 26, 2016, file photo, Democratic presidential nominee Hillary Clinton and Republican presidential nominee Donald Trump appear on a monitor during the presidential debate at Hofstra University in Hempstead, N.Y. Opposition research is a typically inside-the-Beltway term that has burst onto the public stage with the disclosure that President Donald Trump's eldest son was receptive to an offer from a "Russian government attorney" for dirt on Clinton during the 2016 presidential campaign. (AP Photo/Mary Altaffer, File)

By Associated Press July 13, 2017 5 min read

WASHINGTON (AP) – Psst. Wanna hear something bad about your opponent?

As any political strategist can attest, opposition research is a lifeblood of campaigning, with documents, recordings and tips streaming in from all directions claiming evidence of a rival’s misdeeds.

“Oppo research,” as it’s also known inside the Washington Beltway, burst onto the public stage with the disclosure that Donald Trump Jr., the president’s eldest son, welcomed an offer to get dirt on Hillary Clinton from a Russian lawyer. But oppo has been a booming business in political circles for years.

Here’s what it is:

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