[5] As constitutionalist, Davide led the creation of the Legislative branch, and also wrote the most resolutions and the bulk of the 1987 Constitution of the Philippines, becoming its father and primary author.

Public unrest over deteriorating economic conditions and the suppression of political rights, as well as the desire of then-President Ferdinand Marcos to perpetuate himself in power, heralded the declaration of martial law in 1972.

In 1978, he was elected assemblyman for Cebu in the Interim Batasang Pambansa under the opposition party Pusyon Bisaya and became one of martial law's staunch critics.

After the overthrow of the Marcos regime through the People Power revolt in February 1986, then-President Corazon C. Aquino convened the Philippine Constitutional Commission of 1986 and appointed Davide as one of its 50 Commissioners.

When the popular protests spilled into the streets, his timely intervention on behalf of "the welfare and will of the people" by administering the oath of office as president to then-Vice-president Gloria Macapagal Arroyo.

By declaring her the constitutional successor it averted potential violence and military takeover of power, and brought the crisis to an end.

Shortly after his assumption, he was elected vice chairman of the Economic and Social Council (ECOSOC), one of the main organs of the United Nations.

[9] On June 30, 2010, President Noynoy Aquino announced that Davide will head a truth commission that will investigate important issues in the country.

However, it violated the equal protection clause for allowing Davide to only lead in the investigation of the anomalies of the Macapagal Arroyo administration, which just recently ended at that time.

[12][a] In 2011 Davide was awarded one of the highest honours of the Holy See - the Knight Grand Cross of the Pontifical Order of St. Sylvester by decree of Pope Benedict XVI.

[citation needed] He was recognized for his life of principled citizenship and his profound service to democracy and the rule of law in the Philippines.

The World Justice Project works to lead a global, multidisciplinary effort to strengthen the Rule of Law for the development of communities of opportunity and equity.

Davide's father and namesake Hilario Sr. built such a reputation in Argao that the whole immediate family was named the ABS-CBN Bayaning Pamilyang Pilipino of the Year in 1997.

[7] Hilario Jr.'s brother Romulo Davide (born March 1932) is a Magsaysay Awardee and was hailed by the same foundation as the Father of Plant Nematology.

They have five children, namely: Hilario III (a lawyer, former city councilor of Cebu City and Governor of Cebu); Joseph Bryan Hilary (a law graduate), Sheryl Ann (a doctor), Noreen (a Master in SPED graduate), and Delster Emmanuel (an architect) and fourteen grandchildren including namesake Hilario Jose IV, son of Joseph Bryan.