British diplomat Craig Murray has repeatedly said that they met the person who leaked the DNC emails, and that they are a DNC-insider:
"Craig Murray called the CIA claims “BS”, adding: “They are absolutely making it up. I know who leaked them,” Murray said. “I’ve met the person who leaked them, and they are certainly not Russian and it’s an insider. It’s a leak, not a hack; the two are different things.""
https://www.craigmurray.org.uk/archives/2016/12/cias-absence-conviction/

This whole "Russian hack" thing has been fake propaganda, just like so much else that the MSM hypes up, like White Helmets in Syria, terrorists being "government opposition," the lack of coverage of the USA-coalition efforts in Mosul, Iraq, which is far worse than Aleppo was, the coverage of jihad / ISIS Twitter personalities in Aleppo as if they're civilians, the claims of Russian annexation of Crimea... Western MSM is fake from head to toe. It's about time that people figure it out.