Veteran administrator and long time Sabah rights advocate Simon Sipaun has died at the age of 88.

His son Ignatius said he passed away from pneumonia and related health complications at 10.41am on Sunday at a private hospital here.

A wake will be held at Agut Jubili Lighthouse in Penampang, while his funeral Mass is set for 10am on Tuesday at the Church of Mary Immaculate.

Sipaun rose through the ranks of the Sabah civil service before becoming State Secretary from 1988 to 1993, the highest administrative post in the state government.

After retiring, he continued in public life, later serving with the Human Rights Commission of Malaysia for about a decade, including a term as vice chairman.

He remained widely known for speaking out on democracy, governance and civil liberties, and for consistently championing Sabah’s rights under the Malaysia Agreement 1963 through public talks and engagement with political and civil society groups.

Born in Kampung Tuavon, Penampang, he was among early Sabahans to study overseas under the Colombo Plan, later completing his studies at Victoria University of Wellington.

In 2011, he became the first chairperson of Proham, a civil society group formed by former Suhakam commissioners to promote human rights awareness.

Known for his plain speaking style and firm principles, Sipaun stayed active in public discourse well into retirement, earning respect across political lines for his steadfast stance on state rights and justice.