The Principles of Ruling in the Quran
Contrary to common belief, khilafah has no base in the Quran. This style of ruling was established after Rasulullah. The election style (Bay’ah) of the four caliphs is like a republic, and the leaders are like presidents. Unfortunately later reign and monarchy was insisted on in the Muslim world. The Quran didn’t bring any ruling form. The Quran brought timeless and universal principles about ruling. The principles are:
Justice, neutrality, equal treatment (al-Araf 7:29; al-Maida 5:8, 42; an-Nahl 16:90; an-Nisa 4:58, 135; Saad 38:22, 26).
Qualification (an-Nisa 4:58, 59).
Consultation (Shura) (Al-i İmran  159; Şûra  38).
Accountability of the administrators (Al Imran 3:161; al-Mumtahina 60:12).
Freedom of thoughts and faiths (al-Baqara 2:256; al-Anam 6:107; al-Kafirun 109:6; an-Nisa 4:140).
Stand by the common good (Maruf) and avoid the wrong (Munkar) (Al Imran 3:104).
Prevent the income gap between the rich and poor (al-Hashr 59:7).
Prevent cheating at economy and trade (as-Shuara 26:181-183).
Prevent bribery (al-Baqara 2:188).
Prevent wastage (al-Araf 7:31).