One Nation senator Rod Culleton has penned a bizarre conspiracy-theory-laden letter to the High Court in which he claims armed SWAT teams are helping the banks rob Australians of their assets, complains of a Commonwealth "reign of terror" and slams the judges he's trying to win over as "elitist".

The eccentric West Australian has used his official submission to the court – obtained exclusively by Fairfax Media – as an opportunity to air "all the grievances" he has with the federal government.

And there are many.

He starts by questioning the legitimacy of everything the Federal Parliament has done since 1990, claiming it has breached the constitution because it "has not been constituting itself with the Queen" and changed its name from the Parliament of the Commonwealth to the Parliament of Australia.