In important cases Muhammad ibn Maslamah was deputed by Umar to proceed to the spot, investigate the charge and take action.
On occasions the officers against whom complaints were received were summoned to Medina, and charged in Umar's administrative court.
[3] On discovery of any scandal on the part of any official, an investigation through a special department of accountability headed by Muhammad ibn Maslamah would be carried out and if the official would prove guilty he was immediately deposed from his office and his punishment was vary from publicly humiliating punishments to flogging.
This reform was introduced in 637 A.D. A beginning was made with the Quraish and the Ansars and the system was gradually extended to the whole of Arabia and to Muslims of conquered lands.
In contrast to many post-Roman polities in Europe, grants of land, or of rights to collect taxes directly from the payers, were of only minor importance.
Umar established military cantonments on strategic positions throughout the empire to deal with any emergency efficiently and quickly.
According to the Islamic jurist Al-Ghazali (Algazel, 1058–1111), the government was also expected to stockpile food supplies in every region in case a disaster or famine occurred.
[7] During his Caliphate Umar reinstated the practice of praying tarawih in congregation as there was no longer any fear of people taking it as something mandatory.