Updated at 9:44 a.m.

This week in the Russia investigations: The Senate Judiciary Committee dumps documents about the 2016 Trump Tower meeting, the special counsel's office celebrates its first birthday and the GOP escalates its war against the Justice Department.

The enemy within

After chapters on "wiretaps," eavesdropping, "unmasking" and the Foreign Intelligence Surveillance Act, the new hotness this week was confidential sources.

FBI investigators used a confidential source in the initial phase of their inquiry into overtures made by Russian intelligence agents to people in the Trump presidential campaign.

Law enforcement officials told The New York Times and The Washington Post that the person, who has been identified by name in another report by The Daily Caller, met with campaign aides in 2016 as the FBI was investigating who knew what about the Russian outreach.

For Trump and supporters, the stories are more evidence about improper overreach by the FBI and Justice Department. This is really about President Barack Obama's administration snooping on the opposing party's political campaign during an election year, they argue.

"Wow, word seems to be coming out that the Obama FBI 'SPIED ON THE TRUMP CAMPAIGN WITH AN EMBEDDED INFORMANT,' " Trump wrote on Twitter, adding "If so, this is bigger than Watergate!"

Law enforcement officials have been fighting a rearguard action against Republican leaders in Congress who wanted information about the confidential informant. The FBI had begun taking precautions in case the name was revealed — as it now may have been — to try to protect other active cases connected with the person, per The Post.

Known and unknown

Many questions in the Russia imbroglio have not yet been answered — and some of them may never be. With enough time and detail, however, others do actually get resolved.

The Senate Judiciary Committee released more than 2,500 pages of material this week related to its investigation into the June 9, 2016, meeting at Trump Tower in which Donald Trump Jr. hosted a delegation of Russians. It shed the most light yet on that aspect of the story, and on a few other subplots too.

Here is a rapid-fire look at some questions that have been answered and in many cases, the questions those answers have raised.

Did the Trump campaign get political intelligence from Russia? Yes. Trump Jr. and his compatriots didn't get potent "dirt" on Hillary Clinton as they expected, according to the Judiciary Committee materials, but they did get something else: Russian attorney Natalia Veselnitskaya gave a tip about what she called illicit money transfers involving two American investors, the Brothers Ziff.

The people in the meeting who spoke to the Judiciary Committee said they didn't feel they could use that in the campaign. And they didn't understand what Veselnitskaya was talking about when she went on to complain about the Magnitsky Act sanctions that have pinched elite Russians since the Obama administration.

Were there other transactions like this between the Trump campaign and the Russians?We don't know. There were contacts — Page flew to Moscow and then-Sen. Jeff Sessions met with Russia's then-ambassador to the United States, among others — but no conspiracy has been established definitively. President Trump, Trump Jr., and everyone else involved denies there was any conspiracy connecting the Trump campaign to the active measures the Russian government was waging against the United States.

Did President Trump actually reimburse his lawyer for the payments to Stormy Daniels?Yes.We asked last week, based on a document released by Daniels' lawyer, whether Russian billionaire Viktor Vekselberg might have covered the payment supporting the non-disclosure agreement about her alleged sexual encounter with Trump, an encounter the president denies. And to be clear, a company linked to Vekselberg did pay Trump's lawyer, Michael Cohen, although that company now denies its link to Vekselberg. But Trump himself this week listed his reimbursements to Cohen in his latest financial disclosures, apparently confirming that aspect of the story.

So what did the Vekselberg-linked payments to Cohen actually buy?Good question.Here's another: What happened to the suspicious activity reports about Cohen that had reportedly been compiled inside the Treasury Department? That was another subplot this week; The New Yorker reported that a leaker inside federal law enforcement had released one of three reports on Cohen because two of them had gone missing.

But the Treasury Department said on Thursday that it sometimes limits access to these reports if they are sensitive, suggesting that the Cohen material might not have disappeared as part of a cover-up. Instead, maybe the special counsel's office considers them so hot it didn't even want other special agents or investigators to see them.

In typical imbroglio fashion, this answers one question while raising yet another:

Who's been helping Stormy Daniels' lawyer, Michael Avenatti?Now we know — sort of.We broached that question last week and now it's clear there is someone inside Treasury or elsewhere in the law enforcement world who has been leaking confidential financial records. Somehow they made their way to Avenatti and formed the basis of his memo.

Which leads to another question: What else could be in Cohen's bank records?

Infiltration, cont'd

In January, we asked whether "infiltration" might be the new "collusion" — whether the next line of advance in this story might involve attempts by Russian intelligence to co-opt American political organizations in 2016.

There have been reports for awhile about the outreach by one now-sanctioned Russian government official via the National Rifle Association, and the Senate Judiciary Committee materials released this week confirmed there's yet more evidence about that which isn't yet public.

"The committee has obtained a number of documents that suggest the Kremlin used the National Rifle Association as a means of accessing and assisting Mr. Trump and his campaign," as the Judiciary Committee's Democrats wrote.

At least one of those "documents" is already out in the open. It's an email to Sessions and campaign aide Rick Dearborn from NRA member Rick Erickson describing the desire of the Russian government to use the NRA as a back channel to the Trump campaign.

Democrats on the House intelligence committee quoted that email in their response to the majority report by the Republicans on that committee released earlier this year. Now the Senate Judiciary Committee's Democratic minority is suggesting there is more here.

How much more? To what end? Were any other American political organizations involved — as intermediaries, or beneficiaries of "straw donors" or in some other way? For every question in this saga that appears to be resolved, at least one more opens up.

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