The article convincingly describes some rather underhanded behavior by federal law enforcement appearing to violate 4th Amendment rights. Of course it's hard to empathize with criminals, well, because of their crimes. At the same time it's not hard to want to protect the rights of the people from overzealous police. It would be ideal for attorneys and other experts to comment on this case.
As portrayed in the article, an appellate court decision that the use of "Stringrays" requires a warrant before they are deployed would be a step in the right direction. I think there should be more restrictions on technologies that can grab thousands of communications at a time.