By now, few American leaders -- other than President Donald Trump, on occasion -- dispute that Russia interfered in the 2016 U.S. presidential election. What remains unproven is whether anybody from Trump’s winning campaign assisted in that interference. A wide-ranging criminal investigation that has produced indictments against Russian nationals and former Trump advisers hasn’t directly tied any of the Americans to Russia’s influence campaign, but it has produced hints that some people in the Trump campaign at least wanted to play ball.

1. What clues might point to the campaign’s involvement?

The most intriguing one at the moment involves Roger Stone, a political operative who advised Trump. He hinted during the 2016 campaign that he knew in advance that the anti-secrecy group WikiLeaks would release unflattering information hacked from the campaign of Trump’s rival, Hillary Clinton. Since that hacking was carried out under the guidance of Russian intelligence, according to U.S. investigators, Stone -- who was arrested on Jan. 25 on charges of witness tampering and making false statements -- is seen as a possible link between Trump and the Russian election meddling. Furthering that idea, Trump’s onetime personal lawyer, Michael Cohen, now says that he overheard Stone tell Trump that he was communicating with WikiLeaks founder Julian Assange about “a massive dump of emails that would damage Hillary Clinton’s campaign.”

2. What was in those emails?

First, WikiLeaks released almost 20,000 emails from inside the Democratic National Committee that showed how staffers there had favored Clinton during the primary against Bernie Sanders. That prompted the resignation of the DNC’s chairman, Debbie Wasserman Schultz. Later, WikiLeaks released tens of thousands of emails from the Gmail account of John Podesta, Clinton’s campaign chairman; this email dump is the one that Stone seemed to know was coming. The material hacked from Podesta produced unflattering headlines about Clinton saying politicians “need both a public and private position” on tough issues; Clinton allegedly being fed in advance a question that would be posed during a televised debate; and Clinton speaking of her “dream” of “a hemispheric common market, with open trade and open borders.” Looking back on her defeat, Clinton said the “WikiLeaks email dumps” had been “like Chinese water torture.”

3. What other clues are there?

Paul Manafort, chairman of Trump’s campaign for two months, may have shared polling data with an associate tied to Russian intelligence. Former Trump foreign policy adviser George Papadopoulos pursued Russia’s help in the campaign and interacted with a suspected Russian agent who promised compromising information about Clinton. And as Trump was sewing up the Republican Party’s nomination in June 2016, a Russian lawyer offering information on Clinton was granted a meeting at Trump Tower in New York with Trump’s eldest son, Donald Jr.; Trump’s son-in-law, Jared Kushner; and Manafort.

4. What does Trump say?

He insists that no evidence will emerge of “collusion,” which in legal terms would translate to conspiracy. Trump dismisses as a “total hoax” the suggestion that his campaign welcomed Russian interference.

5. Who’s investigating?

Robert Mueller, a former Federal Bureau of Investigation director, was called back into service as special counsel to oversee the probe. Eight days before his appointment, Trump had fired the head of the FBI, James Comey, who’d been a key player in the investigation. Mueller’s team of investigators and prosecutors have charged six former Trump advisers, 26 Russian nationals and three Russian companies. Five of the six former Trump advisers have pleaded guilty, though none to charges of helping Russia interfere with the election. Stone, the sixth, has vowed to fight his charges in court.

6. When will Mueller announce his conclusions?

Soon, by all indications. As a special counsel, he must conclude his work with a report spelling out who was and wasn’t prosecuted, and why. That confidential report goes to the attorney general; there’s no requirement that it gets shared with Congress or the public. (One exception: The attorney general must explain to the House and Senate Judiciary Committees any instances in which the special counsel was blocked from taking certain actions.) If the opposition Democratic Party, which now controls the House, makes good on its promise to demand Mueller’s full report from the Justice Department, there could be a legal fight, with the White House asserting executive privilege.

7. How did this all begin?

In April 2016, Democratic Party leaders called in a cybersecurity firm to look at suspicious software on their computers. The firm said it found digital footprints of hackers tied to the Russian government. The Democratic National Committee went public with the news and the suspicion of Russian involvement in June of that year, just after Clinton clinched the party’s nomination for president, and just after Assange said his group had ”upcoming leaks in relation to Hillary Clinton.”

8. And WikiLeaks got those emails from Russia?

That’s the allegation. U.S. intelligence agencies concluded that Russian President Vladimir Putin ordered a campaign to undermine “public faith in the U.S. democratic process” and Clinton’s candidacy, and that along the way, Putin and his government “developed a clear preference” for Trump. Russia’s efforts included hacking and leaking the emails that undermined Clinton’s campaign, plus using phony accounts and advertising on Facebook and Twitter to sway American public opinion. U.S. intelligence says Russia’s General Staff Main Intelligence Directorate, or GRU, gave the emails to WikiLeaks through an intermediary. Some of the emails also were released through the “persona” of a purported Romanian hacker, Guccifer 2.0, and a website, DCLeaks.com, both of which promoted the hacked information to certain journalists.

9. How does Assange respond?

From the Ecuadorian embassy in London, where he lives under political asylum, Assange has denied that the Russian government was his source of the hacked emails. But an indictment released by Mueller in July 2018, charging 12 Russian military intelligence officers allegedly assigned to disrupt the U.S. election, said that WikiLeaks asked Guccifer for the hacked emails in order to help promote them in advance of the Democratic National Convention, and that Guccifer responded with instructions on how to access them.

10. What does Putin say?

The Russian leader confirmed he did in fact want Trump to win the election but said that was only because Trump was interested in improving U.S.-Russian relations. As for allegations of meddling in the U.S. election, Putin called them “utterly ridiculous.”

11. Which Trump aides are under scrutiny?

Potentially any who had contact with Russian representatives or intermediaries during the presidential campaign. That list includes Trump Jr., Kushner and Stone, plus:

• Manafort, Trump’s onetime campaign chairman, who was convicted of evading taxes on some of the tens of millions of dollars he earned as a political consultant in Ukraine, advising the pro-Russian Party of Regions, in the years before he went to work for Trump.

• Michael Flynn, who lasted just 24 days as Trump’s first national security adviser. In the words of former acting Attorney General Sally Yates, Flynn “compromised” himself -- made himself vulnerable to being blackmailed -- by lying about the contents of a December 2016 phone call with Russia’s ambassador to the U.S. Flynn pleaded guilty to lying about that call to federal agents.

• Carter Page, a U.S. energy consultant once listed by Trump as a foreign policy adviser, whose July 2016 visit to Moscow drew the FBI’s interest.

• Cohen, Trump’s onetime personal attorney, who pleaded guilty to lying to Congress about how deeply into his presidential run Trump was pursuing a real-estate project in Moscow. Cohen’s admission could be used to show Trump had sought to conceal his business interests in Russia. In January 2017, shortly before he took office, Trump wrote on Twitter, “I HAVE NOTHING TO DO WITH RUSSIA - NO DEALS, NO LOANS, NO NOTHING!”

12. Is Trump himself being investigated?

Mueller appears interested in whether Trump obstructed justice by firing Comey as FBI director in May 2017; allegedly asking Comey, days earlier, to go easy on Flynn; and allegedly asking Comey for a pledge of loyalty. Then there’s Trump’s personal involvement in the drafting of a misleading statement that tried to spin the June 2016 Trump Tower meeting -- the one that included his son, son-in-law and a Russian lawyer -- as being about international adoptions. In November, Trump’s legal team submitted written answers to questions posed by Mueller’s team.

To contact the reporter on this story: Laurence Arnold in Washington at larnold4@bloomberg.net

To contact the editors responsible for this story: Kevin Whitelaw at kwhitelaw@bloomberg.net, Larry Liebert, Lisa Beyer

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