The Chichen Itza is a Wonder that was built by the Mayans in real life. It requires Jurisprudence and this wonder reduces crime in a civilization by 30%. The Chichen Itza is a place where the Mayans would do there human sacrifice so this is the reason why crime gets reduced. People would see the ritual sacrifice and then become discouraged about doing a crime.
Chichen Itza (CTP2)

The Chichen Itza from the Great Library