He was a Filipino nationalist. He served as Senator of the Philippines, Secretary of Justice, founding chair of the Commission on Human Rights, and founder of the Free Legal Assistance Group. Diokno is the only person to top both the Philippine Bar Examination and the board exam for Certified Public Accountants (CPA). His career was dedicated to the promotion of human rights, the defense of Philippine sovereignty, and the enactment pro-Filipino economic legislation.
In 2004, Diokno was posthumously conferred the Order of Lakandula with the rank of Supremo?the Philippines' highest honor. February 27 is celebrated in the country as Jose W. Diokno Day.