Short answer. No. Article 114 of the Revised Penal Code says no person shall be convicted of treason unless on the testimony of at least two witnesses to the same overt act, or on the accused's confession in open court. A single witness to the act is not enough to sustain a treason conviction.
What the law says
No person shall be convicted of treason unless on the testimony of two (2) witnesses at least to the same overt act or on confession of the accused in open court.
Revised Penal Code, Article 114 — Treason Against The Philippines. Read the full provision →
The two-witness rule
Treason carries a special evidentiary safeguard that most crimes do not. Article 114 provides that no person shall be convicted of treason unless on the testimony of two (2) witnesses at least to the same overt act or on confession of the accused in open court. This means one witness, standing alone, cannot support a treason conviction, no matter how credible he seems. The two witnesses must speak to the same overt act — the same concrete act of levying war or giving aid and comfort to the enemy — not merely to different suspicious acts. Testimony about one act plus testimony about a separate act does not satisfy the rule.
The only alternative: confession in open court
The article gives just one substitute for the two witnesses: a confession of the accused in open court. This is a confession made before the court itself during the proceedings, not a statement given to investigators or signed in a police station. An out-of-court admission, however detailed, does not replace the two-witness requirement. The rule is deliberately demanding because treason is among the gravest offenses against the State and historically has been the crime most open to abuse through fabricated or coerced accusations. Requiring either two witnesses to the same overt act or a formal in-court confession is a barrier against convictions built on a single accuser.
Penalty today: read the article as amended
The penalty text must be read in its current form. For a Filipino citizen, Article 114 as amended by Republic Act No. 10951 (2017) sets a fine not to exceed Four million pesos (₱4,000,000); older reproductions of the Code still print outdated amounts, so the figure to rely on is the amended one. The article still names the penalty of death, but Republic Act No. 9346 (2006) prohibits the death penalty in the Philippines. In its place the courts impose reclusión perpetua where the Code's nomenclature is used. So even where treason is proven under the two-witness rule, the punishment actually available today is reclusión perpetua, not death.