Police said members of the Sumulong household all tested negative for gunpowder burns in paraffin tests, said Director Ricardo de Leon, police-community relations chief of the Philippine National Police.
Sumulongs wife, Michelle, 31, was found dead last Thursday, in an apparent suicide, with a gunshot wound in the head in the couples bedroom on the second floor of the Sumulong residence in Barangay San Roque, Antipolo City.
Sumulong told reporters at Michelles wake at the Marianne Memorial Center that she was suffering from "schizophrenia" which triggered bouts of severe depression and made her see, hear and imagine things that were not there.
He belied reports that Michelle was suffering from diabetes, saying its him that is afflicted with it.
He admitted that he had a little argument with Michelle Thursday morning over her refusal to return to the hospital to seek treatment for her mental condition.
Sumulong quoted Michelle as saying, "I never want to go back to that asylum (hospital) again."
He said that he was taking a bath when a shot rang out from their bedroom.
Sumulongs brother-in-law Charles also confirmed to reporters that his sister was suffering from schizophrenia.