According the Davao City Ordinance No. 5004 or Women Development Code of Davao City, whistling at a woman can be deemed as sexual harassment.
The Women Development Code defines sexual harassment as "a form of misconduct involving an act or a series of unwelcome sexual advances, requests for sexual favors, or other verbal or physical behavior of a sexual nature, made directly, indirectly, or impliedly."
The said ordinance considers the following as sexual harassment "Cursing, whistling, or calling a woman in public with words having dirty connotations or implications which tend to ridicule, humiliate, or embarrass the woman such as 'puta (prostitute),' 'boring,' 'peste (pest),' etc."
It was signed and approved by Davao City Mayor Duterte on October 14, 1997. The code is considered a pioneering piece of legislation.
Consequently, sexual harassment is penalized under the Anti-Sexual Harrasment Act of 1995 or Republic Act 7877, and the provision on acts of lasciviousness under the Revised Penal Code.
Incoming head of the Philippine National Police Chief Superintedent Ronald dela Rosa said that "Sa kanya na ‘yan. Siya na mag-explain para doon sa ginawa niya," when asked of his comment on the incident
(That’s his call. Let him explain what he did.)
Atty. Salvador Panelo, spokesman of president-elect says that the latter did not want to offend Mariz Umali, a reporter from GMA-7, when he whistled at her during a press conference on Tuesday.
The incoming presidential spokesperson said that Duterte’s whistling means that the Davao City mayor loves her and that Umali should take it as a compliment.
"Mayor Duterte is a very kind, playful individual. Pag siya'y pumito, ibig sabihin he's fond of you, ibig sabihin mahal ka niya, kaya ka binibiro. Hindi po isang pambabastos yun. On the contrary, the receiver of that should be complimented," Panelo said.