The presidential election court has 180 days from mid-March when Atiku, Peter Obi, and the APM filed their petitions against Tinubu's victory to conclude the hearing and deliver its judgement.
The Presidential Election Petition Court in Abuja has ordered the merger of the cases filed by Atiku Abubakar, Peter Obi and the Allied Peoples Movement (APM) to challenge Bola Tinubu's victory as Nigeria's president-elect.
The five-member panel of the court headed by Haruna Tsammani cited time constraint as the basis for its decision, in a ruling on Tuesday.
The court has 180 days from the time the three petitions were filed in mid-March to conclude the hearing and deliver its judgement.
In a ruling detailing a report of its pre-hearing session on Mr Obi's petition, on Tuesday, the court ordered a consolidation of the three pending petitions.
The panel's chair, Mr Tsammani, citing Paragraph 50 of the First Schedule of the Electoral Act 2022, said the interest of justice would be served by a merger of the petitions.
"The justice of these petitions demands that this petition be consolidated," Mr Tsammani said.
After harmonising the suits, the court ordered Mr Obi and his party to prove their case within three weeks instead of the six weeks they requested for during the pre-hearing sessions.
The court gave Mr Obi 30 May for the commencement of hearing of his substantive petition and he is expected to conclude his case on 23 June.
The court added that it would conduct proceedings on a day-to-day basis from Mondays to Saturdays.
For the respondents in the petition - INEC, APC, Mr Tinubu and Kashim Shettima, the vice-president-elect - they have five days each to present their defence.
On allotment of time, the petitioners have 30 minutes each to lead or cross-examine their or adverse parties' star witnesses. The other witnesses have 20 minutes each to testify and the legal team of the adverse parties will have five minutes each for re-examining them.
Mr Obi had through his lawyer, Livy Uzoukwu, a Senior Advocate of Nigeria (SAN), filed his petition challenging Tinubu's victory on 20 March - 20 days after Mr Tinubu was declared winner of the polls by INEC.
At the time of filing this report, the court had yet to give its report on Atiku and APM's pre-hearing sessions of their petitions.
But all petitioners and respondents must abide by the court's decision consolidating the petitions.
Background
The petitioners - Atiku, Mr Obi and APM - are urging the court to nullify Mr Tinubu's victory owing to alleged rampant malpractices during the conduct of the 25 February presidential election.
They accused the Independent National Electoral Commission (INEC) of manipulating the electronic process in favour of the All Progressives Congress (APC) Mr Tinubu.
Atiku, the presidential candidate of the Peoples Democratic Party (PDP) came second in the race, while Labour Party's Mr Obi came third.
Worried by time constraint, the chair of the panel, Mr Tsammani, reminded lawyers to parties of the need to consolidate the three pending petitions.
Specifically, Mr Tsammani at Monday's sitting said it was bound to conclude proceedings and give judgment on all pending suits by 16 September.
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Responding to the court's concerns, Mr Obi's lawyer, Awa Kalu, reduced the seven weeks to six for his client to present 50 witnesses in aid of their case against Mr Tinubu.
Subsequently, Mr Kalu, a law professor and Senior Advocate of Nigeria (SAN), left the proposed consolidation of the petitions to the court's discretion.
Similarly, INEC's lawyer, Kemi Pinheiro, a SAN, urged the court to use its discretion to determine the harmonisation of the petitions.
Atiku's lawyer, Eyitayo Jegede, a SAN, did not oppose the merger of the suits as his client assembled 100 witnesses to testify for the court.
But Mr Tinubu's lawyer, Akin Olujinmi, a SAN, disagreed with the consolidation of the petitions.
Mr Olujinmi and the APC argued that the interest of justice would not be served as the proceedings would be "unwieldy."
