ABUJA (Reuters) - Nigeria’s chief justice will face trial on Monday for allegedly breaching asset-declaration rules, the Code of Conduct Tribunal (CCT) said on Saturday, a month before a presidential election in Africa’s most populous country.

Chief Justice Walter Onnoghen is the head of Nigeria’s judiciary, which plays a key role in election matters and has helped resolve disputes in past votes.

The conduct tribunal, which tries asset-declaration misdemeanors, said in a statement on Saturday that Onnoghen would face six separate counts, without giving further details.

Onnoghen could not be reached for comment.

Under Nigerian law, state officials must declare their assets before taking office and after they leave. The court did not say why it had brought the charges against Onnoghen almost two years into his tenure.

The Opposition Peoples Democratic Party (PDP) accused the ruling party of plotting to destabilize the judiciary ahead of elections by seeking to remove Onnoghen, which could cause a constitutional crisis.

Nigerians go to the polls on Feb. 16 to elect a new president in an election where incumbent Muhammadu Buhari will seek a second term and is campaigning on his anti-corruption record.

In 2016, the tribunal charged the Senate President Bukola Saraki, the country’s third most-powerful politician, for false asset declaration. Saraki was later cleared of wrongdoing.