Trump's latest target is no puppet for the Democratic party
If Grassley doesn't know this, he might want to check with Jason Foster, Grassley's chief investigative counsel, who has received information Simpson dug up during Foster's time on Judiciary and Foster's previous stint as an investigator for Republican Rep. Dan Burton's House Government Reform Committee.
A Grassley spokesman said Foster "has not had any significant working relationship with Glenn Simpson."
David Bossie, a conservative activist who worked with Foster on the Burton committee, praised Simpson to Bill O'Reilly back then for exposing that McAuliffe protected himself from probes by giving "a lot of information to reporters." Simpson had shown how McAuliffe "cashed in" on labor ties.
Simpson's foreign-money investigations infuriated politicians of all stripes. With Jill Abramson (later top editor at the New York Times), he helped break key stories about John Huang, Webb Hubbell and overseas Asian interests giving big campaign gifts to Democrats.
After the 9/11 terrorist attacks, Simpson probed terrorism financing. Then he went to Brussels under Journal bureau chief Peter Fritsch (now his Fusion partner) and became fascinated with Russian money. In March 2007, he wrote to Paul Manafort with a prescient inquiry, saying he had "credible information" that the future Trump campaign manager represented Ukrainian official Viktor Yanukovych without registering as a foreign agent. A decade later, Robert Mueller indicted Manafort over exactly that.
At Fusion, Simpson has investigated political money for clients of all persuasions, including a hedge-fund manager and more than a few Trump supporters. So it follows that when conservative Paul Singer's Washington Free Beacon and then the Democrats wanted Trump research, Simpson used his intelligence contacts from Brussels to probe Trump's financial ties to Russia.
I don't share Simpson's interest in journalism for hire, nor do I approve of his willingness to take distasteful clients.
But I do know he's a dogged gumshoe with one overriding ideology: distrust of all politicians.
Follow Dana Milbank on Twitter, @Milbank.
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