Omnibus Election Code
Section 200. Challenge based on certain illegal acts. - Any voter or watcher may challenge any voter offering to vote on the ground that the challenged person has received or expects to receive, has paid, offered or promised to pay, has contributed, offered or promised to contribute money or anything of value as consideration for his vote or for the vote of another; that he has made or received a promise to influence the giving or withholding of any such vote or that he has made a bet or is interested directly or indirectly in a bet which depends upon the result of the election. The challenged person shall take a prescribed oath before the board of election inspectors that he has not committed any of the acts alleged in the challenge. Upon the taking of such oath, the challenge shall be dismissed and the challenged voter shall be allowed to vote, but in case of his refusal to take such oath, the challenge shall be sustained and he shall not be allowed to vote.