By dividing the control over the regions into several "kings" , the Maya Civilization separated the control over the society into several fractions that held by each king.
These kings have the power to independently create laws/order for their area of jurisdiction.
In a way, this made the government process become more efficient. But, in exchange of that efficiency, Mayan Society was constantly under threat of conflicts that might occurred between different kings. This shows that they were not a unified empire.
