Who are Paul Manafort and Rick Gates, and why are they in the news today?

Earlier this morning, Paul Manafort and Rick Gates surrendered to the FBI and Justice Department special counsel Robert Mueller. Mueller has been heading the investigation into Russian involvement during the 2016 election, as well as possible connections between Russia and those associated with President Trump.
Manafort and Gates held high positions within the Trump campaign staff. Manafort, a Republican strategist, joined the Trump campaign in March 2016 and was quickly promoted to chairman and chief strategist. These titles granted Manafort control of the entire campaign and its operations.
Gates has been a longtime business associate to Manafort and served as Manafort’s deputy within the Trump campaign.
According to The New York Times, Manafort was fired from the Trump campaign in June 2016 after reports surfaced that he received over $12 million in “undisclosed payments” from Viktor F. Yanukovych, the former Ukrainian president and a pro-Russia politician.
The official FBI indictment of Manafort and Gates also stated that Manafort and Gates acted as “unregistered agents” of several Ukranian parties and interests.
Manafort’s work with the Ukrainians resulted in him being paid tens of millions of dollars. He and Gates have been charged with laundering this money through “scores of United States and foreign corporations, partnerships, and bank accounts,” to hide their earnings from the U.S. government.
Because they hid their wealth in offshore accounts, neither Manafort nor Gates paid U.S. taxes on their Ukrainian earnings.
The indictment claims that Manafort used his offshore money to “enjoy a lavish lifestyle” in the U.S.; the FBI expects that more than $75 million flowed through these offshore accounts and Manafort personally laundered more than $18 million. Gates is expected to have transferred $3 million from offshore accounts to his personal accounts.
Overall, Manafort and Gates have been charged with 12 counts, CNN reports. These counts include (but are not limited to) conspiracy against the United States, conspiracy to launder money, giving false statements, and seven counts of failure to file reports of foreign bank and financial accounts.
Manafort and Gates are the first to be formally charged in Robert Mueller’s Russia investigation.
It should be noted that the illegal activities Manafort is being accused of took place before he joined Trump’s campaign.
However, special counsel Mueller’s investigation is trying to determine if anyone connected to Trump was helping Russia tamper with the 2016 election. This indictment of two key Trump players with Ukrainian and Russian connections could potentially uncover Russian collusion during the campaign.
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The Times reiterates that American intelligence has already proven that Russian president Vladimir Putin headed a “stealth campaign” to spread online propaganda to persuade American voters to choose Trump over Hillary Clinton. Mueller is now trying to determine if any members of Trump’s team were also involved in Putin’s scheme and if Trump firing FBI Director James Comey was an obstruction of justice.
President Trump has denied rumored collusion during the campaign, yet secret meetings between Trump and Russian officials during the election have been uncovered in recent months.
The Manafort and Gates indictment and surrender is a dramatic breakthrough in the Russian meddling investigation. Manafort and Gates made their first court appearance before U.S. District Magistrate Judge Deborah Robinson at 1:30 EST this afternoon, at which time they pleaded not guilty to all charges.