Finally, as to whether respondent’s assent to the initial partition agreement serves as an admission against interest, in that the respondent is deemed to have admitted the existence of co-ownership between him and petitioner, we rule in the negative.
An admission is any statement of fact made by a party against his interest or unfavorable to the conclusion for which he contends or is inconsistent with the facts alleged by him.[38] Admission against interest is governed by Section 26 of Rule 130 of the Rules of Court, which provides:
Sec. 26. Admissions of a party. – The act, declaration or omission of a party as to a relevant fact may be given in evidence against him.
To be admissible, an admission must (a) involve matters of fact, and not of law; (b) be categorical and definite; (c) be knowingly and voluntarily made; and (d) be adverse to the admitter’s interests, otherwise it would be self-serving and inadmissible.[39]
http://sc.judiciary.gov.ph/jurisprudence/2011/march2011/165427.htm
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