system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Did the Jedi Council have legal authority to arrest Chancellor Palpatine?

So yes, Palpatine was engaging in treason by aiding the Separatists, and orchestrating a civil war for his own personal profit. That’s a crime, and they’d have the right to arrest him for it. 

However, they all seemed far more concerned with him being a Sith Lord. 

Hypothetically speaking, if he hadn’t been doing shady stuff, and the Jedi discovered that he was a Sith Lord, what would be the outcome?

Could they legally arrest someone solely on charges of Sith affiliation? 

Can the Jedi get audited by the Galactic High Court if they overstep their authority or jurisdiction?

Is it a crime to be a Sith in the Republic?
gpt
Yes, they have power of arrest, and yes, secretly being the Dark Lord of the Sith while operating in the Republic Government is a crime all on it's own. 

The Sith were assumed extinct, but if they aren't, then they are still, legally speaking, at *war* with the Republic after their last invasion. Which makes Palpatine a spy - guilty of espionage and treason.