Special counsel Robert Mueller had a busy year. His investigation of Russian interference in the 2016 election ramped up on multiple fronts, with subpoenas, indictments and guilty pleas. And he referred some of his cases to federal prosecutors in New York, who also brought charges.
This year saw the first charges against Russians for hacking Democratic targets and spreading propaganda on social media. Mueller also raised the stakes for several associates of President Donald Trump, bringing one to trial and securing guilty pleas and cooperation deals from others.
There’s no telling what 2019 might bring. Perhaps Mueller will drop his final report or bring new criminal charges. But in the meantime, here’s a look back at the key developments from 2018.
January 2018
Bannon, Sessions
Nader
Investigators gained a key cooperator after they confronted Middle East specialist George Nader at a DC-area airport. Nader had connections to Trump’s transition team.
After months of negotiations, Trump was considering a sit-down interview with Mueller at the presidential retreat at Camp David, sources told CNN. Negotiations fell through. Trump’s lawyers sent an extensive letter to Mueller arguing that he did not obstruct justice.
By the end of January
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
February 2018
Things heated up in a big way. Mueller brought the first charges against Russians, indicting 13 people linked to the Kremlin-backed “troll factory” that wreaked havoc on social media.
Pinedo
A fake ID salesman from California named Richard Pinedo pleaded guilty to identity fraud and admitted that he unknowingly aided the Russian trolls with their online exploits.
Manafort, Gates
Mueller ramped up the pressure on former Trump campaign chairman Paul Manafort, hitting him with new charges and securing a guilty plea and cooperation deal from his deputy Rick Gates.
van der Zwaan
A Dutch lawyer linked to Manafort and Gates pleaded guilty to lying to Mueller’s investigators.
By the end of February
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
March 2018
Nunberg
The inner-workings of the probe spilled onto live television when ex-Trump campaign aide Sam Nunberg gave a round of TV interviews declaring his intention to defy Mueller’s subpoena. He soon relented and privately met with investigators and testified before the grand jury.
Rosenstein
Deputy Attorney General Rod Rosenstein publicly defended Mueller from Trump’s attacks. "I don't believe there is any justification at this point for terminating the special counsel,” he told USA Today.
Dowd
Trump’s top lawyer, John Dowd, publicly called for Mueller to end the investigation, and he later resigned from the President’s legal team.
By the end of March
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
April 2018
Cohen
Acting on a referral from Mueller, federal investigators in New York raided the home, hotel room, and offices of former Trump attorney Michael Cohen. Trump lashed out against the move, calling it a “disgraceful situation” and calling the Mueller probe “an attack on our country.”
Giuliani
Trump beefed up his cadre of lawyers, adding former New York Mayor Rudy Giuliani and Jane and Marty Raskin, a husband-and-wife team from Florida who specialize in white-collar crimes.
van der Zwaan
The Dutch lawyer who lied, Alex van der Zwaan, was sentenced to serve 30 days in prison.
By the end of April
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
May 2018
Mueller’s investigation reached its one-year mark. The Justice Department disclosed that the probe into Russian meddling cost $17 million so far, with about $7.7 million spent by Mueller.
Cobb
White House lawyer Ty Cobb left his post and to replace him, Trump brought on Emmet Flood, who was one of former President Bill Clinton’s attorneys during the late-1990s impeachment.
Trump
Trump ramped up his attacks against Mueller, calling his prosecutors “angry Democrats” in charge of a “rigged witch hunt.” He also accused them of trying to hurt him with the midterms.
By the end of May
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
June 2018
Manafort, Kilimnik
Prosecutors brought new charges against Manafort and his Russian business associate Konstantin Kilimnik, accusing the pair of tampering with witnesses who might be called at trial. (Manafort later pleaded guilty to conspiracy to obstruct justice, but Kilimnik lives in Russia, safe from the reach of US courts.) A judge quickly revoked Manafort’s bail, sending him to jail.
Cohen
Facing mounting legal problems from federal investigators in Manhattan, Cohen considered cooperating with the government, a source familiar with the matter told CNN.
By the end of June
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
July 2018
Mueller unveiled indictments against a dozen Russian intelligence officers who hacked Democratic targets in 2016 and shared those stolen materials with WikiLeaks.
Putin
At a summit with Russian President Vladimir Putin in Helsinki, Finland, Trump sided with Putin and dismissed the US government’s assessment that Russia interfered in the 2016 election.
Manafort
Manafort’s trial, for financial crimes unrelated to the Trump campaign, kicked off in Virginia.
By the end of July
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
August 2018
Manafort
After a three-week trial, a federal jury in northern Virginia convicted Manafort on eight counts of tax fraud, bank fraud, and conspiracy. The jury deadlocked on 10 additional counts.
Cohen
On the same day as Manafort’s conviction, Cohen pleaded guilty in Manhattan federal court to eight counts of financial crimes and campaign finance violations. He implicated Trump in an illegal scheme to silence women who accused Trump of affairs. Trump denies the affairs.
McGahn
News broke of White House counsel Don McGahn’s extensive cooperation with Mueller.
By the end of August
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
September 2018
Manafort
In a stunning move on the eve of his second trial, Manafort pleaded guilty and agreed to cooperate with Mueller. He admitted to an extensive overseas money laundering conspiracy.
Papadopoulos
George Papadopoulos, a Trump campaign foreign policy adviser who pleaded guilty in 2017 to lying to investigators about his Russian contacts, was sentenced to 14 days in prison.
Stone
Mueller ramped up his investigation into longtime Trump ally Roger Stone, bringing in more of Stone’s associates for private interviews and testimony before the grand jury in DC.
By the end of September
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
October 2018
Trump
Trump’s lawyers started preparing written answers to a set of questions from Mueller. The questions pertained to possible Russian collusion and other events during the campaign.
Pinedo
Pinedo, the fake ID salesman, was sentenced to six months in prison.
Bannon
Bannon returned for another interview with Mueller’s team, this time reportedly about Stone
Gates
Gates continued helping Mueller with multiple ongoing investigations, according to court filings.
By the end of October
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
November 2018
Whitaker
One day after the midterms, Trump fired Sessions and replaced him with Matthew Whitaker, a loyalist who had publicly bashed Mueller. Whitaker became acting Attorney General.
Cohen
In a stunning twist, Cohen pleaded guilty to lying to Congress about efforts during the 2016 campaign to build a Trump Tower in Moscow. The charge was brought by Mueller’s team.
Manafort
Mueller accused Manafort of breaching his plea agreement and lying during their interviews.
Stone
Draft court documents obtained by CNN revealed that Stone was tipped off by an associate about upcoming WikiLeaks releases — before they became public — during the 2016 race.
By the end of November
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
December 2018
Flynn
One year after Flynn pleaded guilty, Mueller revealed in a sentencing memo that Flynn provided “substantial assistance” to the investigation and at least two other ongoing investigations.
Manafort
Mueller’s team accused Manafort of lying to them during his cooperation sessions. Manafort allegedly lied about his Russian contacts during the campaign, according to court filings.
Cohen
A federal judge sentenced Cohen to three years in prison for his crimes. Cohen told the judge that he broke some laws because he “felt it was my duty to cover up (Trump’s) dirty deeds.”
By the end of December
Sentenced to prison
Convicted
at trial
People pleaded guilty
Defendants charged
Sam Fossum and Em Steck contributed to this report.
Video produced by McKenna Ewen.
Photos: AP/CNN/Getty