What they did (record without permission) is illegal but in this case I believe it was justified since they exposed questionable conduct by PP personnel. It'll be hard, if not impossible  to find 12 people to unanimously find them guilty of 15 felony offenses in this case. 
The prosecutor and his party are no doubt sending a strong message but probably hoping to scare them into a plea deal with the possibility of long prison sentences. Political cronies are exacting revenge for exposing PP questionable business practices to the public.