In law and government, de jure (; , "in law") describes practices that are legally recognized by official laws. In contrast, ("in fact" or "in practice") describes situations that are generally known to exist in reality, even if not legally authorized. The terms are often used to contrast different scenarios, for example, "I know that, de jure, this is supposed to be a parking lot, but now that the flood has left four feet of water here, it’s a de facto swimming pool". 

It is possible to have multiple simultaneous conflicting ("de jure") legalities, possibly none of which is in force ("de facto"). After seizing power in 1526, Ahmad ibn Ibrahim al-Ghazi made his brother, Umar Din, the lawful ("de jure") Sultan of Adal. Ahmad, however, was in practice ("de facto") the actual Sultan, and his brother was a figurehead. Between 1805 and 1914, the ruling dynasty of Egypt ruled as "de jure" viceroys of the Ottoman Empire, but acted as "de facto" independent rulers who maintained a polite fiction of Ottoman suzerainty. However, from about 1882, the rulers had only "de jure" rule over Egypt, as it had by then become a British puppet state. Thus, Egypt was by Ottoman law "de jure" a province of the Ottoman Empire, but "de facto" was part of the British Empire.
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, de jure