P.R. Laws tit. 17, § 147
Complaints or orders issued by a public officer pursuant to an ordinance adopted under §§ 143—151 of this title shall be served upon persons either personally or by registered mail, but if the whereabouts of such persons is unknown and the same cannot be ascertained by the public officer in the exercise of reasonable diligence, and the public officer shall make an affidavit to that effect, then the serving of such complaint or order upon such persons may be made by publishing the same once each week for two successive weeks in a newspaper printed and published in the municipality, or, in the absence of such a newspaper, in one printed and published in Puerto Rico and circulating in the municipality in which the dwellings are located. A copy of such complaint or order shall be posted in a conspicuous place on premises affected by the complaint or order. The rules of evidence prevailing in courts of law or equity shall not be controlling in hearings before the public officer.
History —May 15, 1938, No. 222, p. 429, § 4.