The swearing-in was performed by the Deputy Senate President, Jibrin Barau, who presided over the plenary.
Yohanna, a member of the Peoples Democratic Party replaces Abbo, who was sacked by the Appeal Court last week Monday.
The Court of Appeal, Abuja had sacked Abbo, a member of the All Progressives Congress.
Delivering judgment on Monday, the three-member panel presided over by Justice C.E. Nwosu-Iheme, ordered the Independent National Electoral Commission to issue a Certificate of Return to Yohanna as the duly elected lawmaker representing the area in the National Assembly.
The appellate vacated the tribunal judgment which had earlier affirmed Abbo of the All Progressives Congress as the winner of the senatorial election.
INEC had declared Abbo the winner of the February 25, 2023, parliamentary election.
But aggrieved by the electoral body’s decision, the PDP, Yohanna, went to the tribunal to challenge the outcome of the election.
In its ruling, the tribunal dismissed Yohanna’s petition for lacking in merit.
Not comfortable with the judgment of the tribunal, the PDP candidate, through his counsel Johnson Usman, SAN, approached the Appeal Court.
The Court of Appeal, after hearing arguments from parties, agreed with Usman that based on Section 137 of the Electoral Act, 2022, the results tendered clearly showed that there was no compliance with the Electoral Act.
The court, thereafter, deducted the invalid votes from both parties and found that Yohanna and the PDP won the election by a majority of lawful votes.
In the wake of the judgment, Senator Abbo described it as a coup on democracy but told his supporters to be calm.
Details later…
