A Federal High Court, Abuja, on 18 January 2017 proscribed the group and tagged it as a terrorist organisation.
Nnamdi Kanu, leader of the outlawed Indigenous People of Biafra (IPOB), has requested to be joined in a suit challenging the Nigerian government's proscription of IPOB, his special counsel, Aloy Ejimakor, said on Wednesday.
IPOB is a separatist group agitating for an independent state of Biafra.
A Federal High Court, Abuja, on 18 January 2017 proscribed the group and tagged it a terrorist organisation.
The lawsuit, which Mr Kanu has shown interest in, was reportedly filed at the Court of Appeal, Abuja, against the proscription order.
It was filed by IPOB against the Attorney-General of the Federation, Abubakar Malami, according to the information posted on Twitter by Mr Ejimakor.
It is not clear if the case is part of a fundamental rights suit instituted by Mr Kanu against the government. The exact date the suit was filed is unclear.
Mr Ejimakor did not respond to PREMIUM TIMES enquiries seeking clarifications on the lawsuit.
The lawyer, this newspaper learnt, had, on 5 September, filed a notice at the court, on behalf of the IPOB leader, seeking to be joined as an interested party in the suit.
"Today, I will lead a team of lawyers to the Court of Appeal, Abuja to make a case for Mazi Nnamdi Kanu to be joined as a named party in the appeal against the proscription of the IPOB," Mr Ejimakor tweeted Wednesday morning.
"I will also be in tag-team with SAN Machukwu Ume, who is leading in the mother case against the proscription," he added.
In a notice and grounds of appeal made available to Vanguard newspaper, Mr Ejimakor said the IPOB leader was dissatisfied with the ruling of the Federal High Court which proscribed IPOB.
In the notice and grounds of appeal, Mr Kanu claimed that the proscription of IPOB and its listing as a terrorist organisation based on the court's ex parte order was unconstitutional.
Mr Kanu also argued that his arrest, charge, and prosecution which were predicated on the "said ex parte court order" which was without his notice, violated his constitutional rights, particularly the right to a fair hearing.
He said "the trial court misdirected itself in law and thus occasioned a grave miscarriage of justice that has adversely affected" him by using the phrase in the ruling, 'the judge in chambers may on application made by the Attorney-General... '"
Mr Kanu said the phrase presupposes that the application was to be made as an ex parte application.
"The trial judge lifted the words in small close quotes from Section 2 (1) (c) of the Terrorism Prevention (Amendment) Act, 2013 which had used, 'judge in chambers, not ex parte' in enacting the procedure for obtaining an order of proscription and declaration of an entity as a terrorist organization," he said, stressing that 'ex parte' is different from 'judge in chambers.'
Justices absent
Mr Ejimakor would later announce that justices of the court failed to come to the court for the hearing of the appeal, despite being scheduled to hold on Wednesday.
"Today, the 3-member court of appeal justices failed to come to court to hear the appeal against the proscription of IPOB and my motion for leave to join Mazi Nnamdi Kanu as a beneficial party in the appeal," he tweeted Wednesday afternoon.
The case was later adjourned until 7 March 2023, the lawyer said.
"It is unacceptable to me and SAN Ume," Mr Ejimakor said of the adjournment.
Mr Kanu was previously arrested and released on bail. He had jumped bail in 2017.
He was "intercepted" in Kenya in June, last year, by Nigerian security agents and brought back to Abuja.
The IPOB leader, who standing trial for terrorism at the Federal High Court, Abuja, is being detained by Nigeria's secret police, SSS.