MANILA - Supreme Court justices on Tuesday questioned petitioners challenging the constitutionality of the government’s war on drugs why they deem the campaign illegal despite an explicit provision in the assailed Philippine National Police (PNP) circular providing for the protection of human rights and observance of due process in police operations.

During oral arguments on petitions against the administration's drug war, Associate Justices Estela Perlas-Bernabe and Marvic Leonen pointed out to petitioners' counsels Jose Manuel Diokno and Joel Butuyan that a section of the questioned PNP Command Memorandum Circular No. 16-2016 for Oplan Double Barrel provides that police operations shall conform with the law.

Section 8 of the said memorandum circular provides that “[a]ll operations shall conform with provisions of Republic Act (RA) No. 9165 (anti-drug law), the Rules of Court, and strictly observe the Right of the Accused enshrined in the Bill of Rights under the Philippine Constitution, other allied laws, rules and regulations, as well as the internationally accepted principles of international laws, public policy, and with due observance of human rights."

It also says “...all concerned personnel shall strictly observe the rights of persons arrested, detained or under custodial investigation pursuant to RA No. 7438 (Rights of Persons Arrested, Detained or under Custodial Investigation) and other existing rules and regulations of the PNP in the promotion of human rights.…”

Leonen said “it’s clear from the text [of the circular] that the instruction of the chief PNP to all operating units is to observe the Rules of Court, Bill of Rights, other statutes, and international obligations.”

Associate Justice Teresita Leonardo-De Castro, meanwhile, pointed out that a provision in the assailed police circular even directs proper coordination among various entities in the conduct of anti-illegal drug operations.

“You feel that the coordination stage is not being followed? For policemen to coordinate with the LGUs (local government units)... barangay anti-drug units… the PDEA (Philippine Drug Enforcement Agency)… and the Dangerous Drugs Board... the media... you also do not believe that these are being followed?" De Castro asked.

Diokno and Butuyan, however, argued that provisions in the memorandum circular only "pay lip service" as the operative words found repeatedly in the circular are "negated" and "neutralized."

• Petitioners vs 'tokhang' slam police memorandum before high court

Diokno said the terms "negated" and "neutralized" are "vague," and may be taken to mean "to kill."

“There is a maxim of construction that words have to be interpreted by how they are used,” Diokno said.

Senior Associate Justice Antonio Carpio, meanwhile, said the term does not only mean "kill," per police definition, as Philippine National Police chief Director General Ronald "Bato" dela Rosa had said it could also mean "surrender, arrested, or killed."

• Carpio: 'Neutralize' does not only mean to kill

Petitioners asserted that the existing police operating manual is enough to address the illegal drug problem, as they argued that the assailed PNP issuance should be nullified by the High Court.

They also urged the Supreme Court to invalidate Department of Interior and Local Government Memorandum Circular No. 2017-112, the Revised Guidelines on the Implementation of Mamamayang Ayaw sa Anomalya, Mamayang Ayaw sa Iligal Na Droga (MASA MASID) issued on Aug. 29.

The circular requires all cities, municipalities, and barangays to establish a "drop box" system of reporting to gather and assess information regarding corruption, illegal drugs, criminality, violent extremism and other threats to peace and security.

Petitioners said the PNP circular expressly authorized the police to kill suspected drug personalities, while the DILG circular violated citizens' right to due process.

In defense of the government, Solicitor General Jose Calida explained that the assailed DILG circular "does not violate the right to be presumed innocent” and is akin to the collection of vital information from informants.

"Such activity can be considered as a legally allowable government activity that taps into the citizenry’s sense of social responsibility to protect their respective neighborhoods,” Calida said in his comment on the consolidated cases.

President Rodrigo Duterte has dialed down his anti-drug campaign, ordering the Philippine Drug Enforcement Agency to take charge of operations. The PNP has since terminated the controversial Oplan "Tokhang," its house-to-house knock and plead operations.

• Duterte: PDEA should lead anti-illegal drug ops
• PNP terminates 'Oplan Tokhang'