MOP, Bk 3, v.4, 47
“8. On the death or during the funeral of any ranking officer of a Bureau, office, agency, or instrumentality of the Government the flags on the public buildings thereof may be ordered at half-mast by the Department Head concerned.”Done at the City of Manila, this twenty-fifth day of August, in the year of Our Lord, nineteen hundred and thirty-nine, and of the Commonwealth of the Philippines, the fourth.