1) the right against self-incrimination — i.e., the right of a person not to be compelled to be a witness against himself — set out in the first sentence, which is a verbatim reproduction of Section 18, Article III of the 1935 Constitution, and is similar to that accorded by the Fifth Amendment of the American Constitution, 12 and 2) the rights of a person in custodial interrogation, i.e., the rights of every suspect "under investigation for the commission of an offense."

 At the core of the controversy is Section 20, Article IV of the 1973 Constitution, 11 to which respondent Judge has given a construction that is disputed by the People. The section reads as follows:

SEC. 20. No person shall be compelled to be a witness against himself Any person under investigation for the commission of an offense shall have the right to remain silent and to counsel, and to be informed of such right. No force, violence, threat, intimidation, or any other means which vitiates the free will shall be used against him. Any confession obtained in violation of this section shall be inadmissible in evidence.

It should at once be apparent that there are two (2) rights, or sets of rights, dealt with in the section, namely:

1) the right against self-incrimination — i.e., the right of a person not to be compelled to be a witness against himself — set out in the first sentence, which is a verbatim reproduction of Section 18, Article III of the 1935 Constitution, and is similar to that accorded by the Fifth Amendment of the American Constitution, 12 and

2) the rights of a person in custodial interrogation, i.e., the rights of every suspect "under investigation for the commission of an offense."

Parenthetically, the 1987 Constitution indicates much more clearly the individuality and disparateness of these rights. It has placed the rights in separate sections. The right against self- incrimination, "No person shall be compelled to be a witness against himself," is now embodied in Section 17, Article III of the 1987 Constitution. The lights of a person in custodial interrogation, which have been made more explicit, are now contained in Section 12 of the same Article III.13

Right Against Self-Incrimination

The first right, against self-incrimination, mentioned in Section 20, Article IV of the 1973 Constitution, is accorded to every person who gives evidence, whether voluntarily or under compulsion of subpoena, in any civil, criminal, or administrative proceeding. 14 The right is NOT to "be compelled to be a witness against himself"

The precept set out in that first sentence has a settled meaning. 15 It prescribes an "option of refusal to answer incriminating questions and not a prohibition of inquiry." 16 It simply secures to a witness, whether he be a party or not, the right to refue to answer any particular incriminatory question, i.e., one the answer to which has a tendency to incriminate him for some crime. However, the right can be claimed only when the specific question, incriminatory in character, is actually put to the witness. It cannot be claimed at any other time. It does not give a witness the right to disregard a subpoena, to decline to appear before the court at the time appointed, or to refuse to testify altogether. The witness receiving a subpoena must obey it, appear as required, take the stand, be sworn and answer questions. It is only when a particular question is addressed to him, the answer to which may incriminate him for some offense, that he may refuse to answer on the strength of the constitutional guaranty.

That first sentence of Section 20, Article IV of the 1973 Constitution does not impose on the judge, or other officer presiding over a trial, hearing or investigation, any affirmative obligation to advise a witness of his right against self-incrimination. It is a right that a witness knows or should know, in accordance with the well known axiom that every one is presumed to know the law, that ignorance of the law excuses no one. Furthermore, in the very nature of things, neither the judge nor the witness can be expected to know in advance the character or effect of a question to be put to the latter. 17

The right against self-incrimination is not self- executing or automatically operational. It must be claimed. If not claimed by or in behalf of the witness, the protection does not come into play. It follows that the right may be waived, expressly, or impliedly, as by a failure to claim it at the appropriate time. 18

Rights in Custodial Interrogation

Section 20, Article IV of the 1973 Constitution also treats of a second right, or better said, group of rights. These rights apply to persons "under investigation for the commission of an offense," i.e., "suspects" under investigation by police authorities; and this is what makes these rights different from that embodied in the first sentence, that against self-incrimination which, as aforestated, indiscriminately applies to any person testifying in any proceeding, civil, criminal, or administrative.

This provision granting explicit rights to persons under investigation for an offense was not in the 1935 Constitution. It is avowedly derived from the decision of the U.S. Supreme Court in Miranda v. Arizona, 19 a decision described as an "earthquake in the world of law enforcement." 20

Section 20 states that whenever any person is "under investigation for the commission of an offense"--

1) he shall have the right to remain silent and to counsel, and to be informed of such right, 21

2) nor force, violence, threat, intimidation, or any other means which vitiates the free will shall be used against him; 22 and

3) any confession obtained in violation of x x (these rights shall be inadmissible in evidence. 23

In Miranda, Chief Justice Warren summarized the procedural safeguards laid down for a person in police custody, "in-custody interrogation" being regarded as the commencement of an adversary proceeding against the suspect. 24

He must be warned prior to any questioning that he has the right to remain silent, that anything he says can be used against him in a court of law, that he has the right to the presence of an attorney, and that if he cannot afford an attorney one will be appointed for him prior to any questioning if he so desires. Opportunity to exercise those rights must be afforded to him throughout the interrogation. After such warnings have been given, such opportunity afforded him, the individual may knowingly and intelligently waive these rights and agree to answer or make a statement. But unless and until such warnings and waivers are demonstrated by the prosecution at the trial, no evidence obtained as a result of interrogation can be used against him.

The objective is to prohibit "incommunicado interrogation of individuals in a police-dominated atmosphere, resulting in self-incriminating statement without full warnings of constitutional rights." 25

The rights above specified, to repeat, exist only in "custodial interrogations," or "in-custody interrogation of accused persons." 26 And, as this Court has already stated, by custodial interrogation is meant "questioning initiated by law enforcement officers after a person has been taken into custody or otherwise deprived of his freedom of action in any significant way." 27 The situation contemplated has also been more precisely described by this Court." 28

.. . After a person is arrested and his custodial investigation begins a confrontation arises which at best may be tanned unequal. The detainee is brought to an army camp or police headquarters and there questioned and "cross-examined" not only by one but as many investigators as may be necessary to break down his morale. He finds himself in strange and unfamiliar surroundings, and every person he meets he considers hostile to him. The investigators are well-trained and seasoned in their work. They employ all the methods and means that experience and study have taught them to extract the truth, or what may pass for it, out of the detainee. Most detainees are unlettered and are not aware of their constitutional rights. And even if they were, the intimidating and coercive presence of the officers of the law in such an atmosphere overwhelms them into silence. Section 20 of the Bill of Rights seeks to remedy this imbalance.

Not every statement made to the police by a person involved in some crime is within the scope of the constitutional protection. If not made "under custodial interrogation," or "under investigation for the commission of an offense," the statement is not protected. Thus, in one case, 29 where a person went to a police precinct and before any sort of investigation could be initiated, declared that he was giving himself up for the killing of an old woman because she was threatening to kill him by barang, or witchcraft, this Court ruled that such a statement was admissible, compliance with the constitutional procedure on custodial interrogation not being exigible under the circumstances.