“The latest intelligence said to show Putin’s involvement goes much further than the information the U.S. was relying on in October, when all 17 intelligence agencies signed onto a statement attributing the Democratic National Committee hack to Russia.
The statement said officials believed that ‘only Russia’s senior-most officials could have authorized these activities.’ That was an intelligence judgment based on an understanding of the Russian system of government, which Putin controls with absolute authority.
Now the U.S has solid information tying Putin to the operation, the intelligence officials say. Their use of the term ‘high confidence’ implies that the intelligence is nearly incontrovertible.”
Source: U.S. Officials: Putin Personally Involved in U.S. Election Hack – NBC News