I have mentioned that, after a long life of serving the hive, changelings can be granted honorary names. At this point in a changeling's life, it may choose to retire, and become a member of the nobility. All noble changelings wear a purple object wherever they go, be it a cloth or an amulet gifted by one of their former targets.
The nobility make up The Council of Elders, which is comparable to a senate, serving as the only (and usually ineffective) check on the queen's power. They make the major decisions concerning new laws, though their word itself isn't law, and any legislation they pass can be vetoed by the queen.
For all intents and purposes, the queen is an absolute power. She can respond to challenges of her authority without due process, as long as she decides that it would be a waste of time or that the crime committed is more than public enough for anyone to have challenged her if they found it necessary.
The only limitation on her power, is that, once she appoints a council member, she cannot revoke their position. Essentially, she can give power, but never take it away. The gift of retirement and an honorary name is a strictly no take backs deal. A council member can only be removed from service by death itself. And I'm willing to believe that some very untimely, very unfortunate, and very bloody accidents have occurred as a direct result of this rule.
The Council members don't have to attend every hearing or session, and can choose to opt out of federal duty, but, they can always change their minds.
This is the only system of government that exists, as far as we can tell.