The case of Stephen Jin-Woo Kim, the government adviser, and James Rosen, the chief Washington correspondent for Fox News, bears striking similarities to a sweeping leaks investigation disclosed last week in which federal investigators obtained records over two months of more than 20 telephone lines assigned to the Associated Press. At a time when President Obama's administration is under renewed scrutiny for an unprecedented number of leak investigations, the Kim case provides a rare glimpse into the inner workings of one such probe. Court documents in the Kim case reveal how deeply investigators explored the private communications of a working journalist - and raise the question of how often journalists have been investigated as closely as Rosen was in 2010. The case also raises new concerns among critics of government secrecy about the possible stifling effect of these investigations on a critical element of press freedom: the exchange of information between reporters and their sources. The latest events show an expansion of this law enforcement technique," said attorney Abbe Lowell, who is defending Kim on federal charges filed in 2010 that he disclosed national defense information. "Individual reporters or small time periods have turned into 20 [telephone] lines and months of records with no obvious attempt to be targeted or narrow." The Obama administration has pursued more such cases than all previous administrations combined.