The Bill of Rights, enshrined in Article III of the 1987 Philippine Constitution, serves as the "charter of liberties" that defines the relationship between the individual and the State. It does not grant rights; rather, it recognizes inherent human rights and imposes a limit on the otherwise sovereign powers of the government.

In the Philippine legal system, these provisions are not self-executing abstractions. They are breathed into life through the decisions of the Supreme Court, which acts as the final arbiter of constitutional meaning.

I. Due Process and Equal Protection (Section 1)

The bedrock of constitutional liberty is the guarantee that "No person shall be deprived of life, liberty, or property without due process of law, nor shall any person be denied the equal protection of the laws."

Substantive vs. Procedural Due Process

Procedural Due Process: Requires "a law which hears before it condemns." In criminal cases, this involves the right to a neutral tribunal and the opportunity to be heard.
Key Case: Ang Tibay v. CIR established the "cardinal primary rights" required in administrative proceedings.
Substantive Due Process: A prohibition against arbitrary or oppressive laws. Even if the procedure is followed, the law itself must have a valid governmental objective.

Equal Protection

This mandates that all persons under similar circumstances should be treated alike.

Key Case: White Light Corp. v. City of Manila struck down an ordinance banning "short-time" stays in hotels, ruling it violated the right to liberty and was an invalid exercise of police power.

II. Searches and Seizures (Section 2)

The right against unreasonable searches and seizures protects the "sanctity of the home" and the privacy of the individual.

The Warrant Requirement

Generally, a search or arrest requires a warrant issued by a judge upon probable cause.

The Exclusionary Rule (Section 3[2]): Known as the "Fruit of the Poisonous Tree" doctrine. Any evidence obtained in violation of this right is inadmissible for any purpose in any proceeding.

Valid Warrantless Searches

The Court has recognized specific exceptions:

Search incidental to a lawful arrest: Limited to the person and the area within their immediate reach.
Plain View Doctrine: The officer must be in a place where they have a right to be and the evidence is inadvertently discovered.
Stop and Frisk (Terry Search): Requires "genuine reason" to believe a crime has been committed or is about to be committed (Malacat v. Court of Appeals).
Consented Search: Must be shown that consent was given voluntarily and intelligently.

III. Freedom of Expression and Religion (Sections 4 & 5)

Section 4 protects free speech, the press, and the right to assemble.

Prior Restraint and Subsequent Punishment

The Court generally frowns upon prior restraint (censorship before expression).

Tests for Restriction:
Dangerous Tendency Test: (Older standard) If speech may cause a small danger.
Clear and Present Danger Test: (Modern standard) Whether the words used create a clear and present danger of a substantive evil that the State has a right to prevent (Chavez v. Gonzales).

Freedom of Religion

The Philippines follows the Benevolent Neutrality approach.

Key Case: Estrada v. Escritor held that the State should protect religious freedom unless it can prove a compelling state interest that justifies the burden on the individual's belief.

IV. Rights of the Accused (Sections 12–22)

The Philippine Constitution is notably protective of the rights of those under investigation or trial.

Miranda Rights (Section 12)

Any person under custodial investigation must be:

Informed of their right to remain silent.
Informed of their right to have competent and independent counsel, preferably of their own choice.
Provided with counsel if they cannot afford one.

Key Doctrine: These rights cannot be waived except in writing and in the presence of counsel.

Right to Bail and Writ of Habeas Corpus

Bail: A matter of right except for those charged with offenses punishable by Reclusion Perpetua when evidence of guilt is strong.
Writ of Amparo & Habeas Data: Modern remedies created by the Court to address extrajudicial killings and disappearances (Enforced Disappearances), going beyond the traditional Habeas Corpus.

V. The Power of Judicial Review

The application of the Bill of Rights is made possible through the Supreme Court’s power of judicial review under Article VIII.

Requisites for Judicial Review

For the Court to rule on a constitutional issue involving the Bill of Rights, there must be:

Actual Case or Controversy: A real conflict of legal rights.
Locus Standi: The party must have a personal stake in the outcome.
Earliest Opportunity: The question must be raised at the trial stage.
Lis Mota: The constitutional question must be the very "lis mota" (cause of the suit) of the case.

Summary Table of Key Concepts

Provision	Core Right	Key Jurisprudential Principle
Section 1	Due Process	Protection against arbitrariness.
Section 2	Search & Seizure	Warrantless searches are the exception, not the rule.
Section 3	Privacy	The Exclusionary Rule (Inadmissibility of tainted evidence).
Section 4	Free Speech	No prior restraint; Clear and Present Danger Rule.
Section 12	Rights under Custody	Miranda Rights; Right to independent counsel.
Section 14	Presumption of Innocence	Proof beyond reasonable doubt is required for conviction.
Section 21	Double Jeopardy	No person shall be twice put in jeopardy of punishment for the same offense.