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Donald Trump is facing tough questions this week over his campaign's ties to Russia — and obstruction of justice for allegedly trying to intervene — but when it comes to investigating Trump, Russia is just the tip of the iceberg. We were reminded Tuesday afternoon just how vast Trump's potential problems are when Forbes' Dan Alexander broke the news that Eric Trump's charitable foundation has been lying to its donors and funneling significant sums of money right into his father's pockets. The Eric Trump Foundation does what appears at first glance to be legitimate charity work, holding golf fundraisers at Trump family courses and then donating the money to Saint Jude's, a famous children's cancer hospital. But the reality, according to the reporting, seems much less above board. More from Vox:

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Comey's testimony kind of proves Trump right. It also damns him entirely. In Trump's charity pitch, he claims to be receiving the use of Trump Organization golf courses and associated amenities for free — making the Eric Trump Foundation an unusually low-overhead charity. Alexander reports that's not the case. And, in fact, the opposite seems to be the case. Based on a review of the relevant paperwork, "it's clear that the course wasn't free — that the Trump Organization received payments for its use, part of more than $1.2 million that has no documented recipients past the Trump Organization. Golf charity experts say the listed expenses defy any reasonable cost justification for a one-day golf tournament." It's the kind of self-dealing and deception that's practically crying out for legal scrutiny, but like much of the rest of Trump's business career, it's unlikely to get it. Republicans in Congress have shown little interest in investigating this or any other Trump financial problems — and we all remember what happened the last time the IRS tried to bring closer scrutiny to nonprofits.

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The Eric Trump Foundation was a way for a kid with a rich and famous dad and no real skills in life to leverage his family connections into doing something useful and getting credit for it. There are lots of similar organizations. What's less normal is the promises he made to the donors. For a few years, Eric would organize charity golf tournaments at Trump properties and be able to do it on the cheap since it was happening at his dad's clubs. But then his dad got wind of the arrangement and altered the deal: "In the early years, they weren't being billed [for the club]--the bills would just disappear," says Ian Gillule, who served as membership and marketing director at Trump National Westchester during two stints from 2006 to 2015 and witnessed how Donald Trump reacted to the tournament's economics. "Mr. Trump had a cow. He flipped. He was like, 'We're donating all of this stuff, and there's no paper trail? No credit?' And he went nuts. He said, 'I don't care if it's my son or not--everybody gets billed.' " Katrina Kaupp, who served on the board of directors at the Eric Trump Foundation in 2010 and 2011, also remembers Donald Trump insisting the charity start paying its own way, despite Eric's public claims to the contrary. "We did have to cover the expenses," she says. "The charity had grown so much that the Trump Organization couldn't absorb all of those costs anymore." Of course, charities incur expenses all the time, but there are two big specific problems with the arrangement. One is that Eric Trump kept saying the money was all going to charity since the clubs and amenities were being comped. The other is that over time, the Eric Trump Foundation's payments to the Trump Organization ballooned to well above the market rate of the services — up to $322,000 in 2015. "Even if the Eric Trump Foundation had to pay the full rate for literally everything," Alexander writes, "Forbes couldn't come up with a plausible path to $322,000 given the parameters of the annual event (a golf outing for about 200 and dinner for perhaps 400 more)."

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