No definitive source, but Isikoff's employer signed on to an amicus brief that agrues there was no violation of 50 USC 421-426.
The below links relate to a brief filed on behalf of 36 news organizations. One of the authors of the brief is Victoria Toensing, who has posed the same points in editorial columns expressing the function of the statute that forbids disclosure of covert operatives.
The brief itself is a 1.5 Mb PDF file - fair warning.
March 23, 2005 brief filed by 36 News organizations <- Arguing "no crime committed"
http://beldar.blogs.com/beldarblog/2005/03/journalists_ami.html <- Commentary
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