G.R. No. L-23827 - Silverio vs. Castro

The November 12, 1963 election for Mayor of Cateel municipality, Davao province, resulted in Pedro Castro receiving 1,769 votes and Santiago Silverio receiving 1,754 votes according to the Board of Canvassers.
Pedro Castro was proclaimed winner, assumed office, and Santiago Silverio filed an election protest on November 23, 1963.
Pedro Castro filed a counter-protest.

Pedro Castro died on May 6, 1964, before the hearing commenced.
Vice Mayor Misael Clamor succeeded to the office of Mayor and intervened in the case on behalf of the protestee (Castro's interest).

The case was heard starting July 6, 1964.
On September 14, 1964, the Court of First Instance (CFI) reversed the Board of Canvassers' result, declaring Silverio winner by 7 votes (Silverio 1,740; Castro 1,733).
Appeal was taken directly to the Supreme Court on questions of law.

Disputed ballots presented by appellant (Castro’s side), grouped as follows:

First Group: 71 ballots for Silverio where spaces for senators/councilors were not filled or partially filled; ruled valid by CFI.
Second Group: 23 ballots subdivided into (a) 15 ballots for Castro rejected as marked due to prefixes, nicknames, and descriptions; (b) 8 ballots for Silverio ruled valid despite similar features.
Third Group: 11 ballots for Castro rejected by CFI based on the conclusion that several ballots were prepared by one person (handwriting analysis).
Fourth Group: 14 ballots including non-candidates voted for, ballots with corrections/erasures, and ballots with other features; mostly ruled valid by CFI except two ballots later found marked by Supreme Court.

Many rejected ballots for Castro contained prefixes/nicknames used as identification marks (e.g., "Egg", "Toli", "Dr." where Castro is not a doctor), which CFI ruled as marking.
Some ballots contained nicknames or titles known to belong to the candidates and were ruled valid.
Handwriting analysis by CFI found resemblance suggesting one person authored multiple ballots leading to rejection; Supreme Court reviewed this premise in detail.
Ballots with erasures and corrections were treated as corrections, not marking, and deemed valid.
The Court found some ballots invalidated by CFI to be valid and vice versa.

Whether the ballots rejected by the CFI as marked due to prefixes, nicknames, or descriptions should be considered valid votes or invalidated.
Whether ballots rejected by CFI on the ground that several were prepared by the same person (handwriting similarity) are valid or invalid.
Whether ballots with corrections, erasures, or votes for non-candidates should be considered valid or invalid.
The proper application of the rules on marking of ballots and principles of liberal construction favoring the voter's intention under the Philippine election law.