The impeachment on December 12 certainly came swiftly, barely a month after Corona's court had ruled on the 6,453 hectare Hacienda Lusita.

However, Corona himself had acknowledged long before that there were serious efforts to oust him.

'It's a very complex situation we have here,' he said in a briefing in January last year. 'There are people who don't want me at all as chief justice. They happen to be against the previous administration [of president Gloria Macapagal-Arroyo] and who apparently are now in favour of the present dispensation [of President Aquino].'

Regardless of Corona's guilt or innocence, the case against him must be viewed against the backdrop of his rift with Aquino's government, and his longstanding links and apparent loyalty to Arroyo.

Few would dispute Corona's credentials for the position of chief justice - as a student, he consistently earned top grades at the Jesuit-run Ateneo de Manila University before obtaining a Master of Laws degree from Harvard. He divided his time between working in the corporate world and inside the seat of political power, Malacanang Palace, providing legal services to three Philippine presidents - the late strongman Ferdinand Marcos, Fidel Ramos and Arroyo. He became a cabinet member and part of the inner circle of the Ramos and Arroyo presidencies.

Throughout, Corona made no secret that a seat in the nation's top court was the pinnacle of his ambition. Towards the close of the Ramos presidency in 1998, it looked as if his wish had been granted, when Ramos endorsed him for a vacancy in the Supreme Court.

Marites Danguilan-Vitug, author of Shadow of Doubt: Probing the Supreme Court, said that Corona's loyalty earned him Ramos' backing.

Unfortunately for Corona, Ramos' endorsement was ruled invalid by the Court, which deemed it a so-called 'midnight appointment' made during the election period at the end of a presidency and banned under the Constitution. The ban is intended to prevent outgoing leaders making late appointments against the wishes of the incoming administration.

Yet after Ramos stepped down, Corona did not have to look far for a job. He was promptly hired as chief-of-staff and spokesman for Arroyo, the newly elected vice-president.

When the 2001 people power uprising swept Joseph Estrada out and Arroyo in to Malacanang Palace, it brought along Corona.

By then, Corona was a veteran political player who apparently enjoyed the perks of power. Vitug quoted Corona as saying: 'When you're a Malacanang official, it just takes one call. If there's an emergency case and you really need an operation, you can call the Heart Centre and you're really prioritised.'

Corona, now 62, had a heart bypass in 1995 and years later a back operation for which Arroyo apparently paid, Vitug said.

Corona continued to covet a seat on the Supreme Court, telling the South China Morning Post in 2001 that he hoped to have Arroyo appoint him. The following year, Arroyo gave him his dream job as an associate justice at the court.

Yet Corona's rise was not complete. In 2010, Arroyo successfully persuaded a Supreme Court dominated by her appointees to change the 'midnight appointments' ban, with the court specifically ruling that appointments to judgeships weren't covered by it.

Amid public indignation, Arroyo promptly appointed Corona as chief justice even though the position was not yet even vacant; the sitting chief justice would only retire days after the presidential election for Arroyo's successor. The media was banned from covering the lame duck president Arroyo swearing in her former chief of staff to the most powerful legal post in the land. Later, Corona said he was 'absolutely unfettered and uncompromised by encumbrances of whatever nature which would in one way or another hinder or impede me in the performance of these public duties. My heart is in the right place and its loyalty is to the Constitution alone.'

Aquino, who had won a resounding victory, promptly snubbed Corona. He refused to be sworn into office by Corona and on June 30, 2010, was instead sworn in by Associate Justice Conchita Carpio-Morales.

The tension between Aquino and Corona heightened after the Supreme Court shot down as unconstitutional Aquino's initiative to investigate Arroyo's alleged wrongdoings via a 'truth commission'.

Corona downplayed the tension, saying: 'The word 'rift' has often been mentioned. Is there a rift between the executive and the judiciary? I don't think so. I think everybody understands, even the president himself, this is the role we have to play under the Constitution.'

After that, the feud seemed to simmer down. But unbeknown to Corona, the Aquino camp was quietly building an impeachment case against him, citing his numerous court decisions siding with Arroyo and dozens of properties held in his wife Cristina's name and those of his three children and son-in-law.

Things came to a head in November last year, when the Corona-led court ordered the Aquino government to allow Arroyo to travel overseas for medical treatment. Corona flew home from Las Vegas to convene the court session, foregoing his ringside seat at world boxing champ Manny Pacquiao's title defence.

Aquino's justice secretary defied the court order and had Arroyo barred from boarding the plane anyway.

Corona's action favouring Arroyo's travel is among the grounds for his impeachment. He has insisted, though, that his impeachment is really an attack on the independence of the court.

On Thursday, with his trial looming, Corona lambasted his accusers: 'The problem with some people - I won't say who - is that they think that I am a thief like them.'

Corona has admitted owning only five properties, including a posh 3,300 square-foot flat that he bought directly off developers Megaworld for a bargain 14.5 million pesos (HK$2.5 million), about half the market value.

Although neither Corona, nor his lawyers, were available for an interview for this report, he once told the Post that his silence in the face of attacks has been misunderstood: 'I'm the most open and I believe the most tolerant (chief justice).'