The famous Lord Acton remarked, quite astutely, Absolute power corrupts absolutely.
Government structures that follow this principle
Make sure that no single branch is invincible.
No one branch gets to have all of its druthers;
Each one must answer to one or more others.
The whole legislature can pass lots of laws
But courts overturn them if they find some flaws.
Some chief executives make their own moves,
But some acts require that the Congress approves.
The most independent branch, the Supreme Court,
Is made up of those whom the others support.
So, by this system, all branches are checked,
And should treat each other branch with some respect.