The electoral commission has nullified the nomination of Wavinya Ndeti as the Wiper candidate in the Machakos governorship race.
The Independent Electoral and Boundaries Commission (IEBC) Dispute Resolution Tribunal annulled Ndeti's certificate on the grounds that she was also a member of Chama Cha Uzalendo (CCU).
"At the time of the nomination of Ndeti, she was a member of both Chama Cha Uzalendo and Wiper party, which is against the law," said the panel.
The ruling followed a successful petition by MCA Peter Kyalo. The petitioner, a member of Wiper, argued that Ndeti should be disqualified from the race.
Ndeti can appeal the decision at the High Court.
Separately, Nyandarua Woman Representative Wanjiku Muhia got a lifeline after the Court of Appeal nullified the certificate issued to her opponent, Faith Gitau, after the Jubilee nominations.
Appellate judges Roseline Nambuye, Daniel Musinga, and Gatembu Kairu further ordered the Jubilee Party to repeat the nominations for the position within two days.
"The nomination of Faith Gitau by the Jubilee Party as the woman representative candidate for Nyandarua County is nullified. The party is directed to carry out a fresh nomination exercise within two days," ruled the judges.
However, they said they would reserve the reasons for cancelling the certificate until June 21.
Their decision escalated the dispute between Ms Gitau and Ms Muhia, which started at the Political Parties' Disputes Tribunal.
During the Jubilee nominations on April 26, Gitau was declared the winner with more than 31,000 votes.
In the Machakos case, Kyalo argued that Ndeti joined Wiper on April 6, a day after the deadline for party-hopping.
The petitioner submitted that to allow Ndeti's nomination was to set a bad precedent as it would open the door for other time-barred defectors.
IEBC Chairman Wafula Chebukati said the complaint had merit.
"Ndeti is a party leader of CCU and a member of Wiper party and at the time of her nomination, she was still a member of the two parties," said Kyalo.
"After analysing the submissions of the complainant and the respondent, we have concluded that the appeal is merited and is, therefore, allowed," said Chebukati.
Kyalo said Wiper allowed a stranger to participate in its primaries, in violation of the Elections Act.
Ndeti has, however, dismissed the claims, saying her nomination is valid.
She wants the complaint dismissed, arguing that the application is a witch-hunt as it reopens issues that have already been determined.
"My lawyers are working on an appeal which I will file first thing tomorrow (Friday) morning. I would have filed it tonight (Thursday) if it were possible," Ndeti said.