The Philippine Senate has removed an ally of former president Rodrigo Duterte as the chamber’s president and elected a new leader, just weeks before the ​expected start of the impeachment trial against Vice President Sara Duterte, the ex-leader’s daughter.

During a special session yesterday, all 13 senators present voted to select Senator Sherwin “Win” Gatchalian as ‌Senate president, after Senator Joel Villanueva, a member of the pro-Duterte majority, agreed to switch sides. Members of the opposing pro-Dutertre bloc did not attend.

The vote confirms the removal of Alan Peter Cayetano, the leader of the pro-Duterte camp in the Senate, who was elevated to the top post in a “leadership coup” on May 11. On June 3, a bloc led by Gatchalian hit back, mustering the support to declare the Senate’s leadership posts vacant. They failed to elect a ​replacement due to a lack of votes, but both the House of Representatives and the presidential palace acknowledged Gatchalian as acting president of the 24-seat chamber.

An hour before the start of yesterday’s session, Rappler reported, Cayetano announced that he had given up his claim to the Senate presidency, after Villanueva informed him of his decision to support Gatchalian.

Until then, Cayetano and his bloc had disputed Gatchalian’s acting Senate presidency, describing his maneuver on June 3 as an “an illegal coup d’état” and insisting that Cayetano was the “legitimate and moral” Senate president.

All of this political jostling is related to the bitter and protracted political feud that has raged between President Ferdinand Marcos Jr. and the family of former President Duterte over the past two years.

This political war has now come to center on the Senate, which is set to begin the impeachment trial of Vice President Duterte on July 6. Duterte was impeached by the House of Representatives on May 11 for a range of crimes, including corruption, misuse of government funds, and an alleged plot to assassinate Marcos.

If convicted by the Senate, which requires the vote of at least 18 of the 24 senators, she would be removed from office and banned from elected office for life. Duterte and her supporters claim that the impeachment is a politically motivated attempt to neutralize her run for the presidency in 2028.

The tug-of-war between pro- and anti-Duterte blocs in the Senate has spawned a number of subplots that have kept Manila’s large press corps busy for weeks. Cayetano’s election to the Senate presidency was only made possible after Senator Ronald “Bato” dela Rosa, who had been in hiding to avoid an arrest warrant from the International Criminal Court (ICC), made a surprise appearance at the Senate to cast the crucial deciding vote. He was then forced to flee after Philippine police attempted to arrest him on the ICC warrant, which is related to his role in President Duterte’s violent “war on drugs.” Duterte was arrested on an ICC warrant in March 2025 and is currently in a detention cell awaiting trial at The Hague-based court. Dela Rosa is currently in hiding.

Separately, Jose “Jinggoy” Estrada, another pro-Duterte Philippine senator, surrendered to police on June 1 after a special anti-graft court ordered his arrest over a charge that he received 573 million pesos ($9.3 million) in kickbacks in connection with the country’s long-running infrastructure corruption scandal. Before his surrender, Estrada claimed that he was being targeted for being aligned with the Dutertes and that the charges were an attempt to get him to switch sides.

Villaneuva is also being investigated by the Department of Justice for his role in alleged corruption related to flood control projects. Whether this had anything to do with his decision to vote with the anti-Duterte bloc in yesterday’s Senate vote will no doubt be a subject of widespread speculation.