How Donald Trump became 'Individual 1' in Robert Mueller's Russia investigation

After months of quiet, steady progress, Robert Mueller’s painstaking investigation into Russian meddling in the 2016 election is entering a new phase after publicly revealing it was closing in on its ultimate target. It came in a paragraph of legalese inside a nine-page court filing.
“Cohen discussed the status and progress of the Moscow Project with Individual 1 on more than the three occasions Cohen claimed to the Committee, and he briefed family members of Individual 1 within the Company about the project,” it reads.
With those lines in a plea deal with Michael Cohen, Donald Trump’s long-time fixer and lawyer, Mr Mueller moves into uncharted territory. For “Individual 1” is the President of the United States, making him, his family and his business a major subject of interest in the criminal investigation.