'Strong' paper trail has John Durham investigating the months before Mueller appointment

A trail of documents has reportedly led Attorney General William Barr’s handpicked federal prosecutor to focus his inquiry into the origins of the Russia investigation on the first several months of President Trump’s tenure.

John Durham, a U.S. attorney from Connecticut, is zeroing in on the period spanning from January 2017, when Trump took office, to May of that year. A “strong” paper trail, as CBS News senior investigative correspondent Catherine Herridge put it on Friday, has led the investigation into possible misconduct by federal law enforcement and intelligence officials to that time frame.