Why is the FISCR 16-01 Ruling Wrong?

In FISCR 16-01, the FISA Court of Review disagreed with every other federal court. Every previous court to consider the question found a pen register cannot be used to record the body of calls because it might accidentally collect content. Instead, the FISA Court of Review decided law enforcement could record everything, as long as they don't use the content.

From a civil liberties perspective, this is exceedingly worrying. It allows a pen register to be used as a "backdoor warrant" which collects Fourth Amendment protected content without any of the required protection. Under FISCR 16-01, a pen register (which cannot be refused by a judge) can be used to record the entire contents of calls. While the contents are not admissible in court, they could be used in parallel construction or other questionably legal methods of acting on inadmissible evidence.

FISCR 16-01 effectively sidesteps the Fourth Amendment by allowing law enforcement to investigate anyone they wish at any time. This could be used for everything from harassing dissidents to unmasking whistleblowers to harassing personal enemies. The use of searches as an extra-judicial punishment is fundamentally the reason the Fourth Amendment exists. Before the American Revolution, British officials would attempt to silence speech by ordering searches of the homes of dissidents. The searches were not intended to find anything, but to be extra-judicial punishment. Our founding fathers, in writing our Bill of Rights, remembered how search could be used as a tool of oppression. Thus they included a requirement that the government, before intruding into the lives of private citizens, justify any intrusion.

Further, the Supreme Court has previously held that knowing the government may be listening can have a "chilling effect" on free speech. For example, if citizens know the government may be listening, they will restrict the opinions they express because they fear retaliation for having the “wrong” views.