Section 243. Issues that may be raised in pre-proclamation controversy - Omnibus Election Code

(a) Illegal composition or proceedings of the board of canvassers;

(b) The canvassed election returns are incomplete, contain material defects, appear to be tampered with or falsified, or contain discrepancies in the same returns or in other authentic copies thereof as mentioned in Sections 233, 234, 235 and 236 of this Code;

(c) The election returns were prepared under duress, threats, coercion, or intimidation, or they are obviously manufactured or not authentic; and

(d) When substitute or fraudulent returns in controverted polling places were canvassed, the results of which materially affected the standing of the aggrieved candidate or candidates.