Niger’s highest court lifted the immunity of the country’s democratically elected president, Mohamed Bazoum, nearly a year after he was overthrown by mutinous soldiers, his lawyer said Friday, opening the door for the military junta to prosecute him for alleged high treason.

Bazoum and his family have been under house arrest since a military coup that overthrew his rule last summer.

The junta authorities said they planned to prosecute him for “high treason” and for undermining national security, and earlier this year initiated legal proceedings to lift his immunity in a newly created State Court, which became the country’s highest judicial authority.

Before Bazoum was forcibly removed from power, Niger was the West’s last major security partner in the Sahel, the vast region south of the Sahara Desert that has become a hot spot for violent extremism.

But the military junta ordered the withdrawal of Western troops from the country and turned to the Russian mercenary group Wagner for security assistance.

U.S. forces are poised to leave by the middle of September, the Pentagon said earlier this month.

The proceedings before the State Court have been marred by serious irregularities, including violations of Bazoum’s rights to present evidence in his defense, to communicate with his legal counsel, and to be heard before an independent court, according to Human Rights Watch, a leading rights group.

Bazoum’s lawyer, Reed Brody, criticized the ruling as a “mockery” of the rule of law in Niger. “We never even got to speak to our client,” Brody said. “This is a travesty of justice.”

Bazoum’s lawyers have been unable to communicate with him since last October and have had restricted access to case material, according to HRW.

Late last year, the highest court of West African regional bloc ECOWAS ruled that Bazoum and his family were arbitrarily detained and called for him to be restored to office.