admission by silence

An act/declaration made in the presence and within the
hearing/observation of a party who does/says nothing when
the act/declaration is such as naturally to call for
action/comment if not true, and when proper and possible for
him to do so, may be given in evidence against him.

The rule that the silence of the party against whom a claim or
a right is asserted may be construed as an admission of the
truth of the assertion rests on that instinct of our nature,
which leads us to resist an unfounded demand.

When Applicable
This rule applies in both criminal as well as in civil cases.

1. He must have heard or observed the act or declaration of
   the other person
2. He must have had the opportunity to deny it
3. He must have understood the statement;
4. He must have an interest to object, such that he would
   naturally have done so, as if the statement was not true
5. The facts are within his knowledge
6. The fact admitted or the inference to be drawn from his
   silence is material to the issue.

Gabriel vs. Baens 56 Phil 314
Rationale Behind Rule On Admission By Silence
The reason is the recognized rule that if a man remains silent
when he ought to speak, he will be debarred from speaking later.
Qui tacet consitere videtur or silence means consent.

Exceptions To The Rule On Admission By Silence Or 
Instances Where There Is No Admission By Silence
1. Where no good reason exists for the party to comment on the
   act or declaration as when the act or declaration was not
   specifically directed to the party who remained silent.
   (80 A.L.R., Anno., 1272)
2. When the party had no opportunity to comment on the act or
   (People v. Ranario, 49 Phil. 220)
3. Where the act or declaration was made in the course of an
   official investigation.
   (People v. Tia Fong, 98 Phil. 609)
4. When silence is upon advice of counsel.
   (People v. Kozlowski, 115 A.L.R.1505)

The rule on admission by silence applies where a person was
surprised in the act or even if he is already in the custody
of the police.

Voluntary participation in a reenactment of the crime conducted
by the police is considered a tacit admission of complicity.

However, for a reenactment to be given any evidentiary weight,
the validity and efficacy of the confession must first be
shown. The implication of guilt is not derived from mere
silence but from appellant’s silent acquiescence in participating
in the reenactment of the crime.

The rule DOES NOT apply if the statements adverse to the party were
made in the course of an official investigation, as where he was
pointed out in the course of a custodial investigation and was
neither asked to reply nor comment on such imputations or
where the party had a justifiable reason to remain silent, as
where he was acting on advice of counsel, otherwise his right
to silence would be illusory.

No admission can be implied from silence where the failure to
answer was caused by constraint, or the party was not aware at
the time that he had an interest, or believed that he had no
interest, or was only indirectly affected, or where as the matter
was presented, he had no interest to object, for example, where
the statement was not addressed to him or was in his favor.

The same absence of relevancy occurs where an answer would be
unseemly interruption of orderly proceedings then in progress,
such as the delivery of a sermon, the taking of the deposition
or of testimony in open court or the discharge by a judge,
magistrate, counsel, or other person of his proper function in
court proceedings

A person under investigation for the commission of an offense has
the right to remain silent and to be informed of that right.

The rule applies to adverse statements in writing if the party was
carrying on a mutual correspondence with the declarant. However,
if there was no such mutual correspondence, the rule is relaxed
on the theory that while the party would have immediately
reacted by a denial of the statement were orally made in his
presence, such prompt response can generally not be expected if
the party still has to resort to a written reply.