The Kenya National African Union (KANU) led by Baringo Senator Gideon Moi has lost prime land it occupied for 49 years.
Justice Grace Kemei ruled that the land belonged to the Murang'a County Government and neither KANU nor a private developer owned it.
The judge added that the independence party and the tycoon failed to prove ownership of the land and both were considered trespassers.
"The businessman and KANU failed to table any evidence before me to support their claims that they leased or owned the land," she declared.
She also ruled that a title deed presented by the businessman was invalid. The Murang'a tycoon had argued that he purchased the land from a private firm.
KANU on its end argued that it had occupied the land since 1972 and that the conflict arose when the businessman sued them in 2013.
The judge also heard that the land suit was one of the many suits KANU was battling in court.
Evidence presented before Justice Kemei indicated that the contested Murang'a land was registered under the Salvation Army Church in February 1972.
The church had leased the land for 33 years, from July 1964.
In 1975 it wrote to the Commissioner of Lands saying that it wanted to surrender the parcel to Murang'a County Council.
However, the commissioner failed to pursue the matter and no action was taken.
After the first lease expired in 1997, the church applied to extend the lease for 99 years up to 2096.