Section 18(1)(d) in The Disputed Elections (Prime Minister And Speaker) Act, 1977
(d)that the result of the election, in so far as it concerns the returned candidate, has been materially affected-(i)by the improper acceptance of any nomination,or(ii)by any corrupt practice committed in the interests of the returned candidate by an agent other than his election agent,or(iii)by the improper reception, refusal or rejection of any vote or the reception of any vote which is void, or(iv)by any non-compliance with the provisions of the Constitution or of this Act or of any rules or orders made under this Act, the Authority shall declare the election of the returned candidate to be void.