Last week, Rep. Justin Amash, R-Mich., introduced an amendment to the Defense Appropriations Bill. It required the NSA and other government agencies merely to obey the Patriot Act, not the Fourth Amendment. That the data to be collected are "relevant to an ongoing national security investigation" doesn’t mean that there is probable cause that the person whose records are collected has committed a crime.
The NSA and its defenders say that even the Patriot Act doesn't give them enough power. Read my op-ed about it below.