Atiku's legal team sparred with the lawyers to Mr Tinubu, INEC, and APC in the final legal fireworks in court, on Tuesday, over the credibility of the 25 February presidential election.
The Presidential Election Petition Court in Abuja has reserved judgement in Atiku Abubakar's petition challenging President Bola Tinubu's victory.
Haruna Tsammani who led the five-member panel of the court said on Tuesday that a date for judgement in the suit would be communicated to parties.
The electoral commission, INEC, had on 1 March declared Mr Tinubu of the All Progressives Congress (APC) winner of the 25 February presidential election.
But Atiku of the Peoples Democratic Party (PDP) urged the court in his petition to nullify Mr Tinubu's victory on grounds of non-compliance with the Nigerian constitution and the Electoral Act.
Earlier at Tuesday's proceedings, INEC's lawyer, Abubakar Mahmoud, urged the court to dismiss Atiku's suit for "lacking in merit."
In INEC's final argument, Mr Mahmoud told the court that Atiku "failed to discharge the burden placed on him by law" in proving his allegations against the conduct of the election.
He contended that Atiku's case centred on alleged "non-compliance with the electoral act and INEC guidelines and regulations" which the petitioner did not substantiate.
The electoral umpire's lawyer said the deployment of the Bimodal Voters Accreditation System machines and INEC Results Viewing (IReV) for the presidential election was "successful."
"The evidence (before the court) showed that these innovations around accreditation and authentication were successful.
"The information generated by BVAS were stored on the Amazon Web Services (AWS). The evidence before court showed that AWS is the secure and reliable Amazon services across the world," Mr Mahmoud argued against Atiku's claim that the IReV portal was compromised by INEC in favour of Mr Tinubu.
Asked by the court to clarify issues around electronic transmission of results and uploading of results on IReV, Mr Mahmoud explained that Atiku and the PDP "contrived in their mind an electronic collation system. The evidence does not support that. There is no such thing."
He further said "the glitch which disrupted the real-time upload (of presidential election results from the polling units) only lasted for 4 hours 50 minutes on election day."
"Second point of disagreement is that this glitch was contrived as a result of human interference. But Atiku failed woefully to establish that there was human interference.
"The evidence before the court showed clearly that the election went well smoothly at the polling units and results were well collated," Mr Mahmoud told the court.
On the issue of statutory requirement of 25 per cent votes in Abuja, Mr Mahmoud said the argument "is illogical" as it goes against the express provisions of the Constitution.
"The FCT must be treated as if it were a State. We submit that the case for noncompliance has not been made, the FCT argument has to fall on its face," the lawyer argued, praying the court to "dismiss this petition."
Manual results collation didn't detract electoral credibility
In Mr Tinubu's closing argument on Tuesday, his lead lawyer, Wole Olanipekun, said manual collation of the presidential election results did not diminish the credibility of the electoral process
"Uploading results to IReV whether manually or electronically plays no role in collation of results; it does not add or decrease the number of votes. Collation is physical and manual," Mr Olanipekun, a Senior Advocate of Nigeria (SAN), said.
He contended that Atiku had "abandoned his petition,"owing to his inability to prove his case.
Mr Olanipekun told the court that Atiku resorted to "attacking" Mr Tinubu's person instead of proving his allegations.
"The court cannot give to the petitioners what they have not asked in their final written address. It is my submission that Atiku is a meddlesome interloper."
He told the court that Atiku won a paltry one quarter of the two-thirds of votes in Abuja as stipulated in the constitution.
Drawing the court's attention to the issue of mode of transmission of results, Mr Olanipekun said a recent judgement of the Court of Appeal in Lagos, "affirmed the discretion of INEC to apply any methodology in transmission of results."
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"We urge your Lordships to dismiss this petition," Mr Olanipekun argued, adding Atiku merely dumped electoral documents on the court without proving his suit against Mr Tinubu.
The APC on its part, urged the court to dismiss Atiku's petition for lacking in substance.
APC lawyer and ministerial nominee, Lateef Fagbemi, said Atiku's "witnesses did not dispute the figures (results) reeled out" by INEC.
"No one presented an alternative figure of results to counter INEC's declaration."
Mr Fagbemi, a SAN, argued that the issue of 25 per cent votes in FCT "will give overbearing privilege to FCT voters over and above a majority of Nigerians."
He prayed the court to affirm Mr Tinubu's victory and dismiss Atiku's petition for lacking in merit.
With the close of arguments in the case on Tuesday, judgement has to be delivered before 16 September when the suit will lapse.
The petition was filed on 21 March but hearing in the substantive matter began in May, lasting for three months.
