Simple:
Lying to local law enforcement is not a felony. In fact, the penalties for lying to local PD vary depending on the jurisdiction, are at the local prosecutor's discretion, and could be just a fine.
However, lying to the FBI is a felony. So it's pretty obvious why Conservatives don't want their people talking to the FBI; because Conservatives simply can't help themselves from lying to federal agents. They all saw what happened to Flynn, Manafort, Gates, and Papadopolous when they lied to the FBI, and they don't want that to happen again.
So there's a lot of bad faith posturing going on, like your bad faith question here.
You obviously know that there's no federal statute when it comes to lying to local law enforcement; a cursory Google search would reveal that.
So that begs the obvious question; why are you acting in bad faith?
The answer is because you simply don't know how to act any other way.