By Katharine Houreld
ISLAMABAD, Jan 1 (Reuters) - Former Pakistani military ruler Pervez Musharraf went on trial for treason on Wednesday, a case that could test the relationship between an increasingly assertive civilian government and the army.
Musharraf, 70, faces the death penalty over his suspension of the constitution and imposition of emergency rule in 2007, when he was trying to extend his rule as president in the face of growing opposition.
Musharraf, who did not appear in court, says the trial is a politically motivated vendetta.
His lawyers argued that Musharraf cannot get a fair trial in Pakistan because of his history of disputes with the judiciary and the involvement of Prime Minister Nawaz Sharif whom he once overthrew in a coup.
"I am talking of vengeance of a person, my lord," said defence lawyer Anwar Mansoor. "One individual (Sharif) has a bias against the respondent."
Musharraf ousted Sharif in a coup in 1999. Sharif was jailed for a period and then forced into exile. He returned eight years later and won a landslide victory in a May general election.
Musharraf himself stepped down in 2008 to avoid impeachment charges after judges and lawyers led street protests over his attempt to fire the then-chief justice.
It was unclear if Musharraf would eventually appear in court. The trial opened on Dec. 24 but was immediately suspended after a bag of explosives was found on Musharraf's route to the court.
He did not appear on Wednesday because, his lawyers said, explosives had again been found near his house.
Musharraf returned to Pakistan last year, hoping to contest elections that marked the first democratic transfer of power from one civilian government to another in coup-prone Pakistan's history.
Instead, he was barred from standing and enmeshed in a web of legal cases, repeatedly charged and bailed.
In recent days, Musharraf has said in media interviews that the whole army supported him and was upset about his treatment. He also acknowledged that before his return to Pakistan, the army sent a top envoy to try to dissuade him from coming back.
The military is Pakistan's most powerful institution and it has ruled the country for more than half its history since independence in 1947.
But in recent years the civilian government and judiciary have both become more assertive. Top military officers have been questioned although not convicted in human rights and corruption cases.
The military leadership has given no indication it intends to intervene in the trial of Musharraf who was likely to be overstating the army's support for him to help with his legal troubles, said retired general Talat Masood.
"He's trying to twist facts in order to suit his case, to get sympathy and support," he said. "These are tactics to protect and shield himself from the legal process."
Masood said if the case was handled fairly, it could even strengthen relations between the government and military.
"This is a test of civil-military relations," he said. "It is just one instance of the civil government trying to assert itself." (Editing by Robert Birsel and Nick Macfie)