Gaddy is one of the foremost Western experts on Russia's economy and a former adviser to the Russian Finance Ministry in the 1990s. Along with Fiona Hill of Brookings, he is one of the co-authors of a well-regarded book on the personality of the Russian leader, "Mr. Putin: Operative in the Kremlin."
In a blog post published Thursday on the Brookings website, Gaddy outlined his thoughts on the matter. Here is his idea, broken down into four quick points:
1. It was a hacker backed by the Russian government who emailed the German newspaper Süddeutsche Zeitung to offer the leak in early 2015, the initial contact that would eventually lead to the release of the Panama Papers.
2. There's deliberately little information within the Panama Papers that harms Putin: While the $2 billion figure has been reported widely, the link to Putin is relatively obscure, and the Russian president has survived far worse accusations of corruption.
3. Meanwhile, there's plenty of information in the Panama Papers that has already proven extremely embarrassing for other world leaders. At the least, Gaddy argues, this makes Putin and his reputation for corruption seem like less of an outlier and more of standard operating practice.
4. The fact that so few Americans have been linked to the Panama Papers could suggest that their details were deleted from the documents given to Süddeutsche Zeitung and passed on to other media outlets. If this is true, Gaddy suggests that the lack of this information in the release means that it could be being held back for blackmail purposes.
It's a bold claim, Gaddy admitted in an email Friday, and one that he isn't totally sure of himself. "It's certainly not a theory, hardly even a 'hypothesis,' " Gaddy wrote, adding that it was "more a suggestion of something that ought to be seriously investigated."
Even so, this suggestion has caused a bit of a stir in the Russia-watching world.
Karen Dawisha, an academic who also studies Russian corruption closely, tweeted Friday that despite her respect for Gaddy, his latest idea has failed to convince her.
"I'm convinced of everything else Gaddy writes, but not this. Americans aren't n #panamapapers because US hasDelaware"
Others offered carefully worded praise. Russian American journalist Masha Gessen called it "excellent conspirology" on Facebook, while Brian Whitmore of Radio Free Europe/Radio Liberty suggested in a tweet that Gaddy was "trolling" the Kremlin.
There are certainly parts of the idea that make a lot of sense. For one, it seems clear that the $2 billion stuff hasn't really hit Putin hard, while some other world leaders who have fraught relations with Russia - for example, Britain's David Cameron and Ukraine's Petro Poroshenko -- are being seriously rocked by their own links to the scandal.
Why isn't Putin facing a domestic scandal? Well, part of it is simply that Putin is an enormously popular figure in Russia, and it would take a seriously enormous financial scandal to really knock him down.
Additionally, many critics are already sure Putin is corrupt - allegations of the Russian president's wealth go as high as $200 billion, which would easily make him the richest man on earth - and it's hard to see how the relatively loose links between Putin and the $2 billion moved through Panama could really shift anyone's thinking on the matter.
How can we ever know if they are complete? So far everyone seems only to be asking, what secrets are in the Panama Papers?
Of course, there are other parts of the idea that don't fit together.
For one thing, while the lack of US citizens has been widely noted, there are, in fact, a few American links to the Panama Papers. It's also possible that more names could come out as more scrutiny is given to the vast amounts of data in the leak. Or perhaps it's just that Americans prefer tax havens other than Panama (as The Washington Post's Scott Higham reports, US citizens are thought to favor more secure havens such as the Isle of Man, the Cayman Islands and Switzerland).
Gaddy himself acknowledges all of this. However, he also says that even if more and more information is found in the leaks, he's still always going to wonder what might have been left out.
"How can we ever know if they are complete? So far everyone seems only to be asking, what secrets are in the Panama Papers?" he wrote. "We should also ask, are there secrets [in Mossack Fonseca's original files] that are NOT in the Panama Papers?"
Perhaps after years of studying Russia's information wars, it's only reasonable to be a little conspiratorial. Gaddy said he's seen how Putin has used financial secrets "to destroy or to control" people within Russia. And now, when he sees financial secrets creating huge problems for world leaders, he has to wonder if Putin is back to his old tricks again.