Former president Gloria Macapagal-Arroyo leaves the Pasay City court escorted by policemen after attending her arraignment on Thursday and pleading not guilty to charges of electoral fraud. Photo by Erik De Castro, Reuters

MANILA, Philippines (3rd UPDATE) - Ex-Philippine president Gloria Arroyo entered a not guilty plea when she appeared in court on Thursday for the first time since being charged with rigging an election. Arroyo faces life in jail if convicted of conspiring with Andal Ampatuan Sr. to rig the 2007 senatorial elections.

In a statement, Mrs. Arroyo said she willingly submitted herself to the process to clear her name of the charges.

"Despite the continuous and massive vilification campaign against me and my family, I have always said that I will dispute all charges in the proper forum. I am submitting myself to this process not only to clear my name but also as part of my commitment to respect and abide by the rules and orders of our courts. It is my fervent hope that our leaders uphold and our people have faith in the constitution and the rule of law," she said.

Her counsel, Ferdinand Topacio, said the arraignment was very brief after the prosecution agreed to waive the reading of information for her charges.

“Pumayag na rin po ang prosecution na i-waive na o ipagpaliban ang pagbasa ng information sapagkat naunawaan naman po ni Mrs. Arroyo ang pinaparatang sa kanya. At si Mrs.Arroyo po mismo ang tumayo at sinabi niya ‘not guilty,’” Topacio told reporters at the Pasay City Regional Trial Court.

Pre-trial was set for April 19.

Topacio said it was not necessary for Mrs. Arroyo to attend her pre-trial. He called today’s progress as the first step towards the former President’s acquittal.

“The lawyers are studying the case very well, sapagkat sa pre-trial magkakaroon ng stipulation of facts, request for admission, at yung pagbibigay ng mga issues na tatalakayin at babalangkasin sa hukuman, para mapadali ang hearing. An innocent person is languishing in jail eh.”

Arroyo faces life in jail if convicted of conspiring with a feared political warlord to rig the 2007 senatorial election. She has denied any wrongdoing and insists her successor, Benigno Aquino III, is waging a vendetta against her.

"I have peace of mind because my conscience is clear," Arroyo, 64, told a local television station in her last public comments in December.

Court officials said Arroyo, who was arrested in November shortly after authorities stopped her from trying to leave the Philippines, was required to formally answer the charge against her in person at Thursday's hearing.

The vote-rigging case is the first of many charges Aquino has promised to file against his predecessor, whom he has accused of many corrupt acts while she was in power from 2001 to 2010.

Aquino, the son of democracy heroes, won a landslide election victory in 2010 on a vow to fight corruption that has plagued Philippine society for decades but he said worsened dramatically during Arroyo's reign. 

Arroyo has been the top target of his anti-graft campaign.

But three weeks after Arroyo's arrest, Aquino's allies in the lower house of parliament also impeached Supreme Court chief justice Renato Corona on charges of corruption and protecting the ex-president.

The Senate's impeachment trial, which has been going on for a month, has raised political tensions with an influential church group expressing support for Corona and Aquino railing publicly against his foes.

In a speech on Tuesday, Aquino warned his anti-corruption efforts hinged on successful prosecutions of Arroyo and Corona.

"If certain elements are still able to prevent Gloria Arroyo, for example, from being held accountable, then it makes a mockery of our anti-corruption efforts," he said.

"We want to send a stern yet simple message: justice evades no one. There are no exceptions in our campaign against corruption."

Arroyo, who says she is suffering from a rare spinal illness, was arrested at an exclusive hospital three days after immigration authorities stopped her at Manila's airport from leaving the country.

Arroyo's lawyer said then her illness was life threatening, and the Supreme Court under Corona issued an order saying she was allowed to leave the country for treatment.

But Aquino insisted Arroyo was trying flee to evade prosecution and that she was not allowed to leave.

Arroyo, the country's second female president who is now a congresswoman after winning a parliamentary seat in the 2010 elections, was transferred shortly after her arrest to a military hospital.

She has remained at the hospital since, and was charged in December with a second criminal case involving a $330-million telecom deal with a Chinese firm, in which her husband and a political ally allegedly received kickbacks. - with Agence France-Presse