President Rodrigo Duterte shrugged off on Tuesday a plan of Magdalo Partylist Representative Gary Alejano to file a complaint before the International Criminal Court (ICC) after the House of Representatives justice committee dismissed the impeachment complaint against him.

"Yeah, he can go ahead. He is free to do it. This is a democracy," Duterte said in a press conference at the Davao City airport when he arrived from his trip to Cambodia, Hong Kong and China.

But Duterte said several investigations were conducted against his alleged involvement in summary killings even when he was a mayor of Davao City until now. They have proven nothing, he said.

"I was investigated by the (Commission on) Human Rights when Delaila [Leila de Lima] was still the chairman. I was investigated again when she was the Justice secretary. Then I was investigated again by the Senate and I was investigated again by the House. What else do they want…?," Duterte said.

De Lima, now a senator, is a critic of Duterte. She is detained in the national police headquarters in Camp Crame after a warrant of arrest was issued against her by the Muntinlupa City Regional Trial Court for her alleged involvement in the illegal drug trade inside the New Bilibid Prison when she was still the secretary of justice during the Aquino administration.

"Some guys are being taken for a ride a thousand times over. It's true that there were those who were killed...what war on drugs that nobody got killed? But not in the character and kind that I was dished out, that I would order that even a child be killed. That's foolishness. You know me," Duterte said.

The House committee on justice dismissed Alejano's impeachment complaint against Duterte due to lack of substance. The justice committee will come up with a report to be given to be the plenary.

Alejano, a former military officer and ally of Senator Antonio Trillanes, also Duterte's critic, accused the president of ordering the policemen to kill drug suspects. He also charged Duterte of having ill-gotten wealth and for not protecting the country's maritime sovereignty.

After the dismissal of his impeachment complaint against Duterte by the House justice committee, Alejano said he would be compelled to bring the case before the ICC.

The ICC, a court of last resort, tries individuals charged with genocide, war crimes and crimes against humanity.

A Filipino lawyer lodged a complaint before the ICC against Duterte for allegedly commiting crime against humanity in relation to his war on drugs, causing death of over 9,000 people. Celerina Monte/DMS