The Philippines is once again engrossed in an unfolding political drama. The country’s chief justice, Renato Corona, is facing an unprecedented impeachment trial at the Senate for alleged corruption and partiality to the highly-unpopular former President Gloria Macapagal-Arroyo, whose nine-year tenure is seen by many to have been marked by alleged widespread abuses, graft and corruption, not seen since the Marcos regime.

President Benigno S. Aquino III, who was elected on an anti-corruption platform in 2010, sees the Chief Justice’s removal as an important step in his efforts to make corrupt officials in the Arroyo administration accountable for their wrongdoing. Some, however, fear that this might compromise the judiciary’s independence.

Mrs. Arroyo appointed Mr. Corona, her former chief of staff and spokesman, as Chief Justice in the last week of her term, defying precedence. The appointment was widely seen as an attempt by Mrs. Arroyo to dodge prosecution.

Since his appointment, Mr. Corona, along with other Arroyo-appointed justices in the Supreme Court, has been making decisions favorable to Mrs. Arroyo. Among the high profile decisions was the nullification in November of the government’s order to hold Mrs. Arroyo’s departure abroad, pending the conclusion of investigations on her alleged offenses. Mr. Aquino ignored this court ruling, pushing the country to the brink of constitutional crisis resolved only after a lower court judge issued a warrant for Mrs. Arroyo’s arrest.

Following that deadlock, Mr. Aquino mobilized his allies in the lower house of Congress to have Mr. Corona swiftly impeached. The move appears to have been a gamble on Mr. Aquino’s part, for an acquittal could mean that he might spend the remainder of his term as a lame duck. Analysts say Mr. Aquino is counting on public opinion, which is overwhelmingly against Mr. Corona, to push the senators to convict the Chief Justice.

The first two weeks of the trial showed inexperienced congressmen-prosecutors struggling to keep up with the legal acumen of high caliber defense lawyers, which include a former Supreme Court justice. But the drama took a difficult turn on Wednesday, when Mr. Corona asked his colleagues at the Supreme Court to nullify the impeachment proceedings, after prosecutors showed that he has a multi-million bank account that he did not declare in his Statement of Assets, Liabilities and Net Worth (SALN).

Mr. Corona claims the Senate committed abuse of discretion when it ordered the opening of his bank records for public scrutiny, saying it violated the country’s bank secrecy laws. The senators, for their part, warned the Supreme Court not to act on Mr. Corona’s petition on grounds that all matters related to impeachment should be under the sole jurisdiction of the Senate.

“The Senate leadership must carry out its exclusive constitutional mandate of impeachment to its finality. It should not allow its power to be emasculated by another branch,” says Senator Teofisto Guingona III.

Should the Supreme Court grant Mr. Corona’s petition, the Senate would almost certainly ignore the ruling, causing a deadlock between these two political institutions.

Such a constitutional crisis would be very challenging for Filipinos to resolve, and it won’t be the last difficult challenge this political drama would pose for the Philippines.

JJ Domingo is a Manila-based political blogger. He is the author of The Nutbox. You can follow him on twitter (@the_nutbox).