The 1988 Malaysian constitutional crisis was a series of events that began with United Malays National Organisation (UMNO) party elections in 1987 and ended with the suspension and the eventual removal of the Lord President of the Supreme Court, Tun Salleh Abas, from his seat. The Supreme Court in the years leading up to 1988 had been increasingly independent of the other branches of the government. Matters then came to a head when Mahathir Mohamad, who believed in the supremacy of the executive and legislative branches, became Prime Minister.

Mahathir bin Mohamad is a Malaysian politician, author, and physician who served as the fourth and seventh prime minister of Malaysia. He held office from 1981 to 2003 and later from 2018 to 2020 for a cumulative total of 24 years, making him the country's longest-serving prime minister. Before becoming premier, he served as deputy prime minister and in other cabinet positions. He was a member of Parliament for Langkawi from 2018 to 2022, Kubang Pasu from 1974 to 2004, and Kota Star Selatan from 1964 to 1969. His political career spanned more than 75 years, from joining protests opposing citizenship policies for non-Malays in the Malayan Union in the 1940s to forming the Gerakan Tanah Air coalition in 2022.