I hadn't either until someone sent me this youtube video of Judge Andrew Napolitano speaking about it. He said a couple of FBI agents showed up at the 86-year-old librarians house with a search warrant they wrote themselves (as opposed to a judge, as the constitution requires, I thought). They said that she was forbidden by the Patriot Act from telling anyone that she even had been visited by the FBI with the warrant. When she told her 70-some-year-old assistant about it, they both were arrested.
Napolitano said the that federal judge who was assigned the case was about to throw it out, ruling the Patriot Act unconstitutional. Not wanting that, the government withdraw the case against the two women, and without a case before him, the judge could not rule the law constitutional.
This is amazing, and I've been searching the usual databases and fact checkers, but I can find anything to either back up Napolitano and dispute what he's saying:
Here's the video of his speech: