It also directed the Independent National Election Commission to organise fresh election in 15 polling units in the constituency within the next 90 days.
Bello Mashi of the All Progressives Congress was declared the winner of the May by-election.
The chairman of the three-member tribunal, Justice L.M. Boufini, who read the judgment, declared that the petitioner, Nazifi Yusuf of Peoples Democratic Party was able to establish that there was non compliance with appropriate electoral act in the conduct of the election in the said 15 polling units.
He added that the development affected the result of the by-election in the polling units and the overall results.
The tribunal also added that the petitioner was able to establish that the election was characterised by ballot box snatching, violence and over-voting in some of the affected polling units.
The tribunal also agreed with the petitioner that election results from 12 polling units in the Mashi and Dutsi local government areas were wrongly excluded from the overall result.
The affected polling units are Tagura Yamma IIK/G Tagura, Alayida-K/GMAI/Ung, Dankada Makau-K/GDankada, Agala-K/GBage, Agalu-I Primary School, Guarta-K/G Gyarta, FaraII-K/G Fara,Kwankewa-K/G Ayude, Tona-Tashar Kalgo, Badauri III-Kofar Gidan Ma, Bula ArewaII-Primary School and Dantankari Gabas-K/G Miu.
The tribunal chairman declared, “What is invalid remains invalid. The tribunal cannot close its eyes to all these.”
INEC’s counsel, Festus Okoye, in his reaction, said he would report the tribunal’s judgment to the commission; while the PDP lead counsel, Uyi Ugunma, lauded the judgment.