In modern political systems, the legislative branch enjoys somewhat superior position over the other two branches of government, as it reflects the will of the political sovereign. In a parliamentary set-up the legislature is regarded as supreme law-making body on the one hand, and a repository of executive power on the other.
It was in the interest of the provinces to introduce bicameralism in which the upper chamber would represent the federating units on parity basis. Parity of representation in one chamber was thought to act as an important safeguard to preserve provincial autonomy. Another advantage of bicameralism is that the popular trends are let known after short intervals, as the election to both the chambers of Parliament are held at different times. In the form of Senate, a permanent Chamber has been provided in which complete change in it membership shall not take place, as half of its members are elected every three years. The quality of the membership of Senate is expected to be comparatively superior as most competent persons, who may not become members of the National Assembly, due of non-involvement in practical politics, can be elected to the upper chamber due to its limited electoral constituency. Hence, the nation can utilize the services of most talented persons