Mr Obi and the Labour Party, in their filing at the election petition court, accused the INEC and the APC of manipulating election results in favour of Mr Tinubu.
The All Progressives Congress (APC) and the Independent National Electoral Commission (INEC) have asked the Presidential Election Petition Court in Abuja to dismiss Peter Obi's petition challenging Bola Tinubu's victory.
Mr Obi, who was the presidential candidate of the Labour Party, came third in the 25 February presidential election.
He and the Labour Party who are co-petitioners are seeking to upturn Mr Tinubu's victory as Nigeria's president-elect.
Mr Tinubu who was APC presidential candidate polled 8.8 million votes to beat Atiku Abubakar of the Peoples Democratic Party who came second in the race.
Both Atiku, Mr Obi and three other political parties with their candidates are contesting the outcome of the presidential polls, alleging irregularities ranging from INEC's failure to upload election results from polling stations in real-time to its IRev portal.
In particular, Mr Obi and his party accused the INEC and the APC of manipulating election results in favour of Mr Tinubu. They are equally contending Mr Tinubu's failure to secure 25 per cent of lawful votes cast in the Federal Capital Territory (FCT).
But contrary to Mr Obi's claims that the election fell short of provisions of laws, INEC argued that it conducted the polls in strict compliance with the constitution and electoral laws.
The electoral umpire challenged Mr Obi and his party to prove the contrary.
'Obi's petition amounts to waste of time'
But in their separate responses to Mr Obi's complaint, filed Monday night, 10 April, the APC and INEC said the Labour Party and its presidential candidate's petition lacked merit.
They argued that the petition was a waste of judicial time.
Challenging the competence of the petition, Thomas Ojo, a member of the APC legal team being led by Lateef Fagbemi, a Senior Advocate of Nigeria (SAN), argued that Mr Obi was not a genuine member of the Labour Party as at the time of the election.
The APC contended that Mr Obi was a member of the PDP as of 24 May 2022, during which the party screened him as one of its presidential aspirants in April 2022.
"The 1st petitioner (Mr Obi) purportedly resigned his membership of Peoples Democratic Party on 24 May 2022 to purportedly join the 2nd petitioner (LP) on 27th May 2022."
In the filings, the APC recalled that the Labour Party conducted its presidential primary on 30 May 2022, which purportedly produced Mr Obi as its presidential candidate.
The party argued that Mr Obi's nomination as LP's presidential candidate breached Section 77(3) of the Electoral Act.
"The 1st petitioner (Mr Obi) was not a member of the 2nd petitioner (LP) as at the time of his alleged sponsorship.
"Whereas, by the mandatory provisions of Section 77 (1) (2) and (3) of the Electoral Act 2022, a political party shall maintain a register and shall make such register available to the Independent National Electoral Commission (INEC) not later than 30 days before the date fixed for the party primaries, congresses and convention.
"All the presidential candidates of the Peoples Democratic Party (PDP) were screened on 29th April, 2022, an exercise in which the 1st petitioner herein participated and was cleared to contest while being a member of the party.
"The 1st petitioner herein resigned his membership of the PDP on Thursday 26th May, 2022 and joined the Labour Party the following day being 27th May, 2022.
"The 2nd petitioner herein conducted its presidental primary on 30th May, 2022 which produced the 1st petitioner as the candidate it intended to sponsor in the general election."
LP failed to submit Mr Obi's name to INEC 30 days before primaries
Faulting Mr Obi's petition, the APC argued that Section 77(3) of the Electoral Act mandates a political party to submit its membership register to the electoral umpire 30 days before their presidential primary election.
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It said Mr Obi "as at 30 April, 2022, was still a member of the PDP and his name was not and could not have been in the register of members submitted by by..." LP to INEC.
In another basis for challenging the petition, the APC queried why Mr Obi and his party excluded the PDP and its presidential flagbearer, Atiku, from the suit.
It argued that Atiku's right to fair hearing would be breached should the court accede to Mr Obi's prayers to declare him Nigeria's president-elect, thereby nullifying Atiku's votes without hearing him.
Mr Tinubu's legal team is also expected to file his reply to the petition and others filed by Atiku and other petitioners.
the INEC and the APC are also expected to reply Atiku's petition and the rest of the petitions filed at the Presidential Election Petition Court.
