From Declan McCullagh's article on CNET:
Ryan Radia, associate director of technology studies at the Competitive Enterprise Institute, a libertarian-leaning think tank that has criticized CISPA, suggested that it could also allow Homeland Security to monitor the communications of the federal courts and Congress, and intercept tax returns sent to the IRS. Radia added:
While it appears that Rep. Jackson Lee sought to include several safeguards to limit DHS from improperly using and collecting information that flows on federal networks, those safeguards are essentially toothless. Under her amendment, the Secretary of Homeland Security need only "certif[y]" that the collection or interception of information by DHS complies with the various safeguards and limitations. But the Secretary of Homeland Security has the sole discretion to interpret the language of the safeguards as she sees fit. It appears that no judge or legislator can second-guess a Secretary's "certification" that a particular DHS information use accords with the bill's safeguards.