The Bhutto Government's first achievement was the preparation of a Constitution for the country. The most prominent characteristic of this Constitution was that it accommodated proposals from the opposition parties and hence almost all the major political parties of the country accepted it. The National Assembly approved the 1973 Constitution on April 10, 1973, and it came into effect on August 14. Bhutto took over as the Prime Minister of Pakistan from this date and Fazal Ilahi Chaudhry was appointed as the President of Pakistan. The Constitution of 1973 opens with a Preamble. This is the preliminary part of the Constitution in which broad features of the Constitution have been explained. The first Article of the Constitution declares Pakistan as a Federal Republic to be known as the Islamic Republic of Pakistan. Islam was declared as the State religion of Pakistan. Pakistan was to be a Federation of four federating Units, Punjab, Sindh, N. W. F. P. and Baluchistan.
The Constitution was parliamentary in nature. Article 41 of the Constitution lay down that the President was to be the Head of the State. The President was to be a Muslim above 45 years of age and was to be elected by a joint sitting of members of the Parliament for 5 years. He could be re-elected but could not hold office for more than two terms. The President was to act on the advice of the Prime Minister of Pakistan. The President could be removed on the grounds of physical or mental incapacity or impeached on charges of violating the Constitution or gross misconduct. The President was authorized to appoint the Attorney General, Judges of Supreme Court and High Courts, and the Chief Election Commissioners. In the Provincial Government, each province was to have a Governor appointed by the President. The appointment of Federal Ministers and Ministers of the State from amongst the members of the Parliament was at the Prime Minister's disposal.
The 1973 Constitution set up a bicameral legislature at the Center consisting of two Houses, the National Assembly and the Senate. The National Assembly consisted of 200 seats elected directly for duration of five years. The President on the advice of the Prime Minister could dissolve the National Assembly. The Senate was to consist of 63 members; each province was to elect 14 members. In the Provincial Government, each province will have a Governor appointed by the President. The Provincial Assembly for each province consisted of 240 seats for the Punjab, 100 seats for Sindh, 80 seats for N. W. F. P., and 40 seats for Baluchistan.
The 1973 Constitution provided a free and independent Judiciary. The Constitution guaranteed a right to the citizens; to be protected by law, and imposed two duties on them, loyalty to the Republic and obedience to the law. Any person who was found to abrogate or attempt or conspire to abrogate or subvert the Constitution was to be treated guilty of high treason. The Constitution conferred several kinds of fundamental rights to the people such as the right to life, liberty, equality and freedom of speech, trade and association. The Constitution also declared the laws inconsistent with or in derogatory to fundamental rights as null and void.
In light of the previous experience, the Constitution of 1973 was more Islamic in character than the previous ones. Emphasis was made to establish a real Islamic system in all aspects of social life. Keeping this objective in mind, more Islamic provisions were laid down in the Constitution of 1973. The Constitution recognized Islam as the religion of the country and enjoined upon the State to serve the cause of Islam and to bring all existing laws in conformity with Islam. The Islamic Advisory Council was set up to recommend ways and means to bring existing laws of the country in conformity with the Islamic principles.
The Constitution of 1973 remained in force for nearly four years. It was, however, suspended by General Muhammad Zia-ul-Haq, who imposed Martial Law in the country on July 5, 1979. However, General Muhammad Zia-ul-Haq who ran the country with Martial Law passed the Eighth Amendment in the Constitution in 1985. This Amendment empowered the President to dissolve the National Assembly under Article 58(2) b. This Article was later repealed by the Parliament during Nawaz Sharif's era through Thirteenth Amendment introduced on April 1, 1997. The Thirteenth Amendment was in turn repealed by the Legal Framework Order of 2002, which effectively restored the discretionary powers of the President enacted by the Eighth Amendment.