"Gen. Musharraf is accountable to the nation and the constitution," Khan said.
He specifically mentioned Musharraf's decision to suspend senior judges, including the chief justice of the Supreme Court, and detain them after he declared a state of emergency on Nov. 3, 2007. He was apparently concerned they would challenge his re-election as president.
"The constitution was ruined and violated," Khan said. "The judiciary was humiliated. Judges were manhandled physically, confined along with family and children."
The interior minister insisted that the government's decision to put the former president on trial for treason was not a personal vendetta by Prime Minister Nawaz Sharif, who was toppled in a military coup by Musharraf in 1999.
The government didn't indicate it would press charges against Musharraf for his coup, perhaps because the move was retroactively approved by the Supreme Court and parliament at the time.
One of Musharraf's lawyers, Ilyas Siddiqui, said the former president's legal team would decide its strategy once the court formally begins proceedings.
The prime minister said in June that the government intended to try Musharraf for treason, but would consult with other political parties on the move. Senior lawmakers from the two main opposition parties expressed their support for the government's plan to try Musharraf at the time.
Musharraf governed the country for nearly a decade after the 1999 coup but was forced to step down in 2008 after growing discontent with his rule. He left the country soon after. He returned to Pakistan in March after years in self-imposed exile, with the hope of running in the national election that was held in May. But he was disqualified from participating in the vote because of his actions while in power and has spent most of his time battling legal cases.
Musharraf was held under house arrest for months after returning and was only freed earlier this month after he received bail in four other cases facing him. But he is still barred from leaving the country.
The other cases facing Musharraf involve his alleged role in the murder of former Pakistani Prime Minister Benazir Bhutto, the death of a Baluch separatist leader killed by the army, the killing of a radical cleric and the detention of Pakistani judges.