The court said the December 14 primary election in which the senator supposedly won was illegal.
The Senator representing Kogi east, Atai Aidoko, has been ordered to vacate the National Assembly.
A Federal High Court sitting in Abuja on Wednesday, June 13, 2018, ruled that the primary election of the Peoples Democratic Party (PDP) which Aidoko supposedly won was illegal.
The presiding judge, Gabriel Kolawole said the senator was wrongly presented as the PDP flagbearer during the election.
The judgement is as a result of an application filed by another contestant, Air Vice Marshal Isaac Alfa, seeking the court to nullify Aidoko's election.
The judge held that Alfa is the rightful winner the primary election conducted in Idah, on December 7, 2015.
Justice Kolawole also ordered the Independent National Electoral Commission (INEC) to withdraw the Certificate of Return issued to Aidoko.
The Clerk of the National Assembly was also ordered to swear in Alfa to replace the sacked lawmaker.