The Achaemenid Empire had an administrative bureaucracy that ruled over 45 satrapies, meaning provinces of distinct nations. It hosted half the entire world's population. So you might nee dto narrow down your question a little bit. But taking at face value, it was a tradition amongst the Persian elite to provide a certain amount of freedom to the satrapies. One of the three main satrapies along the eastern coast of the Mediterranean Sea, and what is now known as Levant was called Yehuda Medinata. In Aramaic it meant the province of the Jews. The Achaemenenids gave the Jews financial and socio-political freedoms, just like as any other satrapies of the Empire. This is reflected in Cyrus the Great's cylinder held at the British Museum that showcases a universal declaration of freedom of religions and ethnicities. One way of bestowing such a favour upon a nation was to allow them to build their own temples, pray to their own gods, and practice their own laws. So long as tributes were given to the court of the king on a yearly basis and the 'king's eyes and ears' supervising over a satrapy reported fair conditions of the province, the Achaemenids would not interfere in affairs of those nations. In case of laws, noteworthy that the achaemenid laws were not permanent. A king could set up new regulations and laws upon his ascension to the throne. Such as Darius did after the death of Cyrus, Smerdis, and Cambyses II. The laws which were set by a monarch could only be reversed and repealed by the same monarch or in the case of his death, his successor. Note that Artaxerxes I and Artaxerxes II successively ruled over the Achaemenid Empire for about a century. Each one for almost 40 odd years. That means the laws were metaphorically permanent, in their own lifetimes. I do not have much biblical knowledge of the passage you are referencing to, although I am from a Jewish background. I have a phd in history and I have written multiple books on Achaemenid Empire. There goes the source.