This is after the Court of Appeal in Mombasa overruled a decision by the High Court in Malindi, Kilifi County that upheld his win following the August 8, 2017 general election.
While issuing the ruling, Justice Daniel Musinga, said High Court Judge Justice Weldon Korir made a constitutional error by failing to take into consideration the purpose of scrutiny and recount of votes.
In February 21, Muthama's rival Rishad Amana, won his election petition after the election of the Maendeleo Chap Chap MP was nullified.
Justice Korir had also directed the Independent Electoral and Boundaries Commission (IEBC) to pay Amana Sh3 million.
Addressing the press after the ruling in Mombasa on Thursday, Muthama expressed satisfaction saying the will of Lamu West constituents has been heard.