Using or disclosing confidential financial information for gain is called 'insider trading'. Using or disclosing political or policy information for gain is legal. Why?

Aside from the obvious reason that statists exempt themselves from most laws that they enforce on the proles,  why should this be so?

MEGAN MCARDLE: Can You Be Guilty Of Insider Trading Without Personal Gain? “Washington is a city built almost entirely on relationships that are fostered by a robust trade in confidential secrets.”