CBS hired a cybersecurity firm to conduct the analysis. Attkisson, an investigative reporter who has worked at CBS since 1995, said three weeks ago that she thought someone had tampered with her computers.
In an interview with Philadelphia's WPHT radio on May 21, Attkisson said "there could be some relationship" between what has happened to her and to James Rosen, the chief Washington correspondent for Fox News Channel. In what appeared to be a leak investigation, law enforcement officials obtained a search warrant to obtain some of Rosen's private emails and tracked his comings and goings from the State Department.
Attkisson said she had been having problems with a computer in her house since at least February 2011. At that time, she said, she was investigating the Bureau of Alcohol, Tobacco, Firearms and Explosives' "Fast and Furious" gun-smuggling sting operation and stimulus spending on clean-energy projects. Attkisson won an Emmy award for her "Fast and Furious" investigation.
In another leak probe, prosecutors secretly subpoenaed phone records from The Associated Press.
In its analysis, the cybersecurity firm said that whoever tampered with Attkisson's computer "used sophisticated methods to remove all possible indications of unauthorized activity, and alter system times to cause further confusion."