While parallel construction is usually dodgy as hell, it still requires that there be sufficient evidence obtainable through legal means to build a case. It's

While parallel construction is usually dodgy as hell, it still requires that there be sufficient evidence obtainable through legal means to build a case. It's kind of like a journalist getting information off the record from a source. They can't use that for a story, and the only way they can write about it is if they can find enough on the record or on background sourcing or data to be able to back it up.