The three-member panel of justices led by Justice M.F. Shuaibu began sitting on the appeal at about 10am.
While Adeleke is the appellant, Oyetola and the All Progressives Congress are 1st and 2nd respondents in the appeal marked: CA/AK/EPT/GOV/01/2023.
The Independent National Electoral Commission and the PDP are also joined as 3rd respondent and 4th respondents respectively.
The News Agency of Nigeria reports that the Osun State Governorship Election Petition Tribunal had on January 27, voided the July 16, 2022, election that produced Adeleke of PDP as the elected governor.
INEC had declared Adeleke the winner of the election after polling a total of 403,371 votes. He was said to have won in 17 of the 30 local government areas in the state.
But the panel led by Justice Terste Kume, in its judgment, invalidated the election and declared Mr Gboyega Oyetola of APC as the valid winner of the poll.
The tribunal directed INEC to withdraw the Certificate of Return issued to Adeleke and his deputy, Kola Adewusi, both of whom had been sworn in.
It, however, directed that the Certificate of Return should instead be issued to Oyetola.
Justice Kume held that the governorship election was not held in compliance with Nigeria’s Electoral Act. The tribunal also held that the governorship election was characterised by over-voting. It said after deducting the excessive votes, the figure Oyetola polled at the election was 314, 921.
The tribunal, thus, ordered that Oyetola should be returned as governor of Osun State.
NAN reports that INEC, in its earlier results, said Oyetola won in 13 LGAs with 375,027 votes in the July 16, 2022 governorship election.
Fifteen candidates contested for the poll which was keenly contested between Adeleke and Oyetola.
In his petition, Oyetola, the immediate-past governor of the state, had alleged that the election was characterised by over-voting in 749 polling units.
He also argued that Adeleke forged the academic credentials he submitted to NEC to contest for the election.
The tribunal had commenced sitting in August 2022, a few weeks after the governorship election. Oyetola and the APC were petitioners in the case with Lateef Fagbemi, SAN, and Akin Olujimi, SAN, as their lead counsels.
INEC was the 1st defendant, Adeleke the 2nd defendant and PDP as 3rd defendant.
The hearing was still ongoing as at the time of filing the report.