More than 18 months of special counsel Robert Mueller's investigation has netted 199 criminal charges, 37 indictments or guilty pleas, and 4 prison sentences.
Driving the news: Roger Stone, a longtime Trump associate, was arrested on Friday following an indictment in from the Mueller investigation. He was indicted on seven counts, including lying to Congress, witness tampering, and obstructing an official proceeding. Stone said he would be pleading not guilty and that he would not testify against President Trump.
May 17: Deputy Attorney General Rod Rosenstein appoints Robert Mueller as special counsel to the Russia probe.
June 14: Mueller's probe expands to investigate Trump for possible obstruction of justice.
Oct. 30: Manafort and his business partner Rick Gates are indicted on 12 counts, including conspiracy against the U.S. and money laundering.
- The same day, Trump's former campaign adviser, George Papadopoulos, pleads guilty to making false statements to the FBI regarding his contact with Russian leadership. He later claims he misled agents to protect the president.
Dec. 1: Former national security advisor Michael Flynn pleads guilty to "willfully and knowingly [making] false, fictitious and fraudulent statements and representations" to the FBI regarding his conversations with Russian ambassador to the U.S., Sergey Kislyak.
Feb. 16: Mueller indicts 13 Russian nationals and three Russian entities for violating criminal laws to interfere with the 2016 U.S. election.
- The same day, Richard Pinedo pleads guilty to identity fraud for selling bank account numbers to Russians involved in election interference.
Feb. 20: Dutch lawyer Alex van der Zwaan pleads guilty after being charged on Feb. 16 with lying to FBI investigators about his interactions with Rick Gates and an unidentified individual, labeled "Person A" in court documents.
Feb. 22: Mueller files 32 new financial charges, including money laundering and bank fraud, against Manafort and Gates in the Eastern District of Virginia.
Feb. 23: Gates pleads guilty to conspiracy and lying to investigators.
- A federal grand jury also brings a superseding indictment against Manafort, alleging he "secretly retained a group of former senior European politicians to take positions favorable to Ukraine, including by lobbying in the United States."
March 15: Manafort's lawyers file a motion to dismiss Mueller's D.C. indictment.
March 27: Manafort's legal team files a motion to dismiss Mueller's Virginia indictment.
April 3: Alex van der Zwaan is sentenced to 30 days in prison and $20,000 in fines for lying to FBI investigators. The decision marks the first sentencing in Mueller's probe.
April 9: The home, hotel room and office of Trump's personal attorney Michael Cohen is raided by FBI agents.
- The charges against both Manafort and Kilimnik include conspiracy and obstruction of justice in an alleged attempt to influence other testimonies. Mueller also charges Manafort with conspiracy to launder money, acting as an unregistered foreign agent and lying to authorities against Manafort.
July 13: Mueller indicts 12 Russian military intelligence officers for hacking and releasing Democratic emails during the 2016 campaign.
Aug. 21: Manafort is found guilty by a Virginia jury on eight counts of fraud.
- That same day, Cohen pleads guilty in a Manhattan courtroom to eight counts related to tax fraud and campaign finance violations related to the Southern District of New York's investigation. Over the next few months, Cohen reportedly spent more than 70 hours in interviews with the special counsel.
Sept. 7: Papadopoulos is sentenced to 14 days in prison for lying to the FBI.
Sept. 14: Manafort pleads guilty to charges brought by the special counsel and enters into a "cooperation agreement."
Nov. 8: Attorney General Jeff Sessions submits his resignation at the request of President Trump. Sessions' chief of staff Matthew Whitaker, a public critic of the Mueller investigation, is appointed acting AG.
Nov. 20: Trump's lawyers say they've submitted written answers to questions from the special counsel.
Nov. 29: Cohen pleads guilty in the Mueller investigation to lying to Congress about the length and scope of his work on plans to build a Trump Tower in Moscow. Trump's business entanglements are publicly brought into the Mueller investigation for the first time, with Trump himself reportedly referred to as "Individual 1" in court documents.
Dec. 4: Mueller files a memo recommending no prison time for Flynn, citing his "substantial assistance" and cooperation in the special counsel's investigation.
Dec. 7: Prosecutors from New York’s Southern District recommend a "substantial term of imprisonment" for Michael Cohen for campaign finance and tax violations, as well as lying to Congress, despite his cooperation with the investigation.
- Mueller also filed a memo on Cohen stating that he is not taking a position on what amount of prison time Cohen should serve, but said "any sentence of incarceration" the court in New York recommends would be "appropriate."
- Mueller filed a second document revealing that Manafort lied to the FBI and the Special Counsel's Office about his contact with administration officials, a Russian political consultant, a wire transfer, and information related to another DOJ investigation.
Dec. 12: Michael Cohen was sentenced to three years in prison on charges related to campaign finance violations, tax evasion and lying to Congress. In his guilty plea, Cohen claimed then-candidate Donald Trump directed him in 2016 to pay hush money to two women who alleged affairs.
Jan. 25: Roger Stone, a longtime Trump associate, was arrested following an indictment in the Mueller investigation.
Editor's note: This is an updating post.