The Philippines announced its intention to withdraw from the Rome Statute on March 14, 2018, about a month after the ICC launched a preliminary investigation into the situation in the country.

Since the Philippines is no longer a state party to the Rome Statute, the investigation will only cover the period when the treaty was in force in the country—between November 1, 2011, and March 16, 2019.

[2][3] During an October 2016 Philippine Senate inquiry into extrajudicial killings, opposition Senator Leila de Lima presented a witness, Edgar Matobato, a self-confessed former member of the DDS;[4] Matobato testified that the DDS was taking orders from Duterte and claimed that Duterte himself, while he was still mayor of Davao City, had killed a member of the Department of Justice with an Uzi submachine gun.

[15][16] On October 13, 2016, about four months into the Philippine drug war, ICC prosecutor Fatou Bensouda expressed deep concern over reports of extrajudicial killings of alleged drug dealers and users in the Philippines, stating that the ICC would be "closely following developments" in the country to assess whether to open a preliminary examination if necessary.

[20][21] However, in January 2020, Sabio retracted his allegations and requested the ICC to dismiss the charges, adding that his 2017 case was an orchestrated move by the Liberal Party, notably Senators Antonio Trillanes and Leila de Lima, to discredit Duterte;[22] Sabio's request was rejected by the ICC, who asserted that it "cannot effectively destroy or return information once it is in its possession or control".

[23] Inquiries on the drug war were held by the House of Representatives' Quad Committee and the Senate Blue Ribbon sub-committee in October 2024.

[37] This is despite the ICC meant to be complementary to domestic court systems and only prosecute cases only if "when States do not or are unwilling or unable to do"[38] In October 2024, former Senator Leila de Lima said that there is no legal obstacle to prevent the Philippine government's cooperation with the ICC citing Republic Act 9851 or the "Philippine Act on Crimes Against International Humanitarian Law, Genocide, and Other Crimes Against Humanity" including the surrender or extradition of accused persons "to the appropriate international court".

President Duterte justified the withdrawal by accusing the ICC and the United Nations of "crusading" against him and condemning the UN's "baseless, unprecedented and outrageous attacks" on him and his administration.