Justice Koome was appointed the Chief Justice in May 21, 2021, becoming the fifteenth Chief Justice of the Republic and first woman to hold the office.
Prior to her appointment, she was a Judge of Appeal having been appointed in 2012 where she served in Nairobi, Nyeri and Malindi.
She also served as a High Court Judge (2003 – 2011).
She was the Managing Partner at Martha Koome & Company Advocates (1993 -2003) and Legal Associate at Mathenge & Muchemi Advocates (1988 – 1992).
She was also the chairperson of the International Federation of Women Lawyers in Kenya (FIDA-Kenya).
Judge Koome served as the Chairperson of the National Council on the Administration of Justice special taskforce on children matters which reviewed the Children’s Act. Justice Koome was admitted to the Roll of Advocates in 1987. In 2012, she became the first judge to opt for public sessions during her scrutiny by the Judges and Magistrates Vetting Board.
Among her controversial decisions in the Judiciary was the 2017 ruling in which the Court of Appeal bench set aside a High Court decision that found the appointment of returning officers for the October 26, 2017 repeat presidential election to be illegal. The other judges in that bench were Fatuma Sichale, and Erastus Githinji.
Still at the Court of Appeal, in 2019 she was part of a five-judge bench that threw out an appeal by the government against High Court’s decision to order for registration of an of LGBT organization.
At the Supreme Court, she dealt with a landmark case involving President Uhuru Kenyatta’s bid to amend the Constitution –Building Bridges Initiative (BBI).
In a judgment rendered in March 2022 she rejected the application of the basic structure doctrine in Kenya. She also stated that President cannot initiate a Constitutional amendment process through the popular initiative.
