When Jane Mayer published her 10,000-word article about Charles and David Koch in The New Yorker in August 2010, David Koch denounced her piece in print and, as she reports in her new book, “Dark Money: The Hidden History of the Billionaires Behind the Rise of the Radical Right,” a “private investigative firm with powerful political and law enforcement connections was retained.” While there was no hard evidence on who had hired the firm, “clues leading back to the Kochs were everywhere.”

Source: Review: Jane Mayer’s ‘Dark Money,’ About the Koch Brothers’ Fortune and Influence – The New York Times