President Umaru Musa Yar'Adua was flown to King Faisal Specialist Hospital, Riyadh, on 23 November 2009 for treatment of acute pericarditis and other complications. He did not formally transmit a letter to the National Assembly under Section 145 of the 1999 Constitution authorising Vice-President Goodluck Jonathan to act in his place. A 78-day constitutional vacuum followed in which the cabinet — coordinated by Attorney-General Michael Aondoakaa — insisted no transfer was necessary.
On 9 February 2010 the Senate (David Mark) and House of Representatives (Dimeji Bankole) jointly passed a resolution invoking the 'doctrine of necessity' and recognising Goodluck Jonathan as Acting President. Constitutional lawyers were divided: there was no provision in the 1999 Constitution for the legislature to so designate; Section 144 (incapacity) required a cabinet resolution and Senate approval, neither of which had occurred. Nonetheless the resolution was accepted by the military, the federal civil service, foreign governments and the markets.
Yar'Adua returned to Abuja on 24 February 2010 in a still-unconscious state and died on 5 May 2010. Jonathan was sworn in as substantive President the same evening. The doctrine of necessity entered Nigerian constitutional vocabulary as the standing exception that resolved the 2010 crisis without recourse to Section 145.