Kzin Patriarchy is an hereditary kingdom. The Patriarch line of the Chut-Riit (Chut-Rrit) family has ruled the Kzinti for a long time. They built an huge empire with a lot of slave races but was in the end defeated by Humankind in the Man-Kzin Wars.
The term Patriarchy also refers to the all of the Kzin government as well as the Kzinti families with highest status, equivalent to royalty.
The Kzinti drive for conquest made them implacable foes. They built an empire over thousands of years which was so vast that it covered three times the area of Known Space. Many sentient species who desired peaceful contact and trade became Kzinti slaves and meat animals.
The Kzinti occupation on its conquered worlds was an exercise in extremes. On the one hand, Kzinti cared little about their subject races, and so tended to leave them to their own devices, provided they obeyed their laws; on the other hand, an expanding Kzinti population requires a vast amount of space, and the ongoing war effort demanded natural resources, so subject races tended to be pushed together as Kzinti lands grew.
If a crime committed by a member of a subject race was considered a capital or treasonous offence, the usual method of execution was usually a hunt, as Kzinti enjoy the challenge of hunting (and eating non-poisonous) sentients, and make no attempt to hide it. To be fair, they have always demanded the same of their own criminals, with the difference that cannibalism is taboo.