(Bloomberg) -- The trial of Nigeria’s chief justice for alleged improprieties in declaring assets opened in the capital, Abuja, as lawyers and opposition groups condemned the move as an attempt to intimidate the judiciary and spark a constitutional crisis a month before presidential elections.

Chief Justice Walter Onnoghen didn’t attend the opening of the trial on Monday because he wasn’t personally notified as required by law, his counsel told the Code of Conduct Tribunal. Tribunal chairman Justice Danladi Umar adjourned the hearing to Jan. 22 so the summons could be properly delivered. Six charges were filed against the chief justice, the tribunal said in a statement on Saturday without giving details.

The Nigerian Bar Association described the decision to put Onnoghen on trial as an “assault, intimidation and desecration of the judiciary” by government agencies.

The trial comes ahead of the Feb. 16 election, which pits 76-year-old President Muhammadu Buhari against former Vice President Atiku Abubakar, 72, as top contenders. Abubakar’s People’s Democratic Party has accused Buhari and his All Progressives Congress of clamping down on dissent and preparing to rig the vote, which they deny. The president has refused to sign an electoral bill that lawmakers say they passed to ensure the vote is free and fair.

Since neither candidate is expected to concede in the election, the courts may have to play a important role in determining the eventual winner, said Cheta Nwanze, head of research at Lagos-based risk advisory SBM Intelligence.

“What this means is that it is highly likely that the judiciary will have the definitive say via election petition proceedings on who will be the next president,” he said. “Coming after the country’s highest judge at this time raises questions about the motives of the ruling All Progressives Congress.”

Onnoghen took up the post in March 2017, after his appointment had been delayed by Buhari for months following his recommendation by the National Judicial Council. His name was eventually sent to lawmakers for approval by Vice President Yemi Osinbajo when he was acting for Buhari, who was away on medical vacation.

Buhari’s party said any suggestion it was meddling with the judiciary is “baseless” and that the PDP’s commitment to fight corruption is weak. The president and the APC are committed to ensuring free elections in Africa’s biggest oil producer, it said.

Onnoghen couldn’t be reached for comment.

“Any attempt to force Justice Walter Onnoghen to vacate his office, four weeks to an election for which the unpopular Buhari administration has shown every intention to manipulate, is a move pregnant with negative meaning,” Abubakar said in a statement. “Nigeria is still a democracy and not a fascist dictatorship as President Buhari may wish.”

(Updates with start of trial from first paragraph.)

To contact the reporters on this story: Paul Wallace in Lagos at pwallace25@bloomberg.net;Elisha Bala-Gbogbo in Abuja at ebalagbogbo@bloomberg.net

To contact the editors responsible for this story: Karl Maier at kmaier2@bloomberg.net, Dulue Mbachu

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