Qadi ( ) is a judge ruling in accordance with Islamic religious law (sharia

Sharia

Sharia law, is the moral code and religious law of Islam. Sharia is derived from two primary sources of Islamic law: the precepts set forth in the Quran, and the example set by the Islamic prophet Muhammad in the Sunnah. Fiqh jurisprudence interprets and extends the application of sharia to...

) appointed by the ruler of a Muslim country. Because Islam

Islam

Islam . The most common are and .   : Arabic pronunciation varies regionally. The first vowel ranges from ~~. The second vowel ranges from ~~~...

 makes no distinction between religious and secular domains, qadis traditionally have jurisdiction over all legal matters involving Muslim

Muslim

A Muslim, also spelled Moslem, is an adherent of Islam, a monotheistic, Abrahamic religion based on the Quran, which Muslims consider the verbatim word of God as revealed to prophet Muhammad. "Muslim" is the Arabic term for "submitter" .Muslims believe that God is one and incomparable...

s. The judgment of a qadi must be based on ijmah, the prevailing consensus of the Islamic scholars (ulema

Ulema

Ulama , also spelt ulema, refers to the educated class of Muslim legal scholars engaged in the several fields of Islamic studies. They are best known as the arbiters of shari‘a law...

).

The origin of the institution of qadi is the old Arab arbitrator, the Hakam

Hakam

Hakam may refer to:*Al-Hakam in Arabic الحكم means the wise man, referring to the old Arab arbitrators that predated qadis.*Hakam or The National Human Rights Society, a Malaysian human rights organization*Hakham, a wise man, in Judaism*Hakam, Yemen...

, but qualities from officials in areas conquered by Arabs have been added to the structure.
The term qadi was in use right from the time of the Prophet Muhammad

Muhammad

Muhammad |ligature]] at U+FDF4 ;Arabic pronunciation varies regionally; the first vowel ranges from ~~; the second and the last vowel: ~~~. There are dialects which have no stress. In Egypt, it is pronounced not in religious contexts...

, and remained the term used for judges throughout Islamic history and the period of the caliphate

Caliphate

The term caliphate, "dominion of a caliph " , refers to the first system of government established in Islam and represented the political unity of the Muslim Ummah...

s.