On the basis of relationship between the centre and the units, the governments may be classified as unitary and federal. In a unitary government, all the powers of government are vested in the central government whereas in a federal government, the powers of government are divided between the centre and the units.
Their distinctive feature and comparative merits and demerits are given as follows.
1. Concentration of Powers:
A unitary government is one in which all the powers of administration are vested in a single centre. The centre is omnipotent. A unitary state may be divided into small units for the sake of administrative convenience but the units do not have any constitutional status of their own.
In other words, the constitution does not confer any powers on the units. It is the central government which delegates certain powers to the units on its own accord. The units are, therefore, subordinate agents of centre.
The powers enjoyed by them are the gifts of the centre and as such these can be taken back at any moment. The units are thus not autonomous and independent in any way.
2. Single Government:
In a unitary government, there is a single set of governmental apparatus. There is a single supreme legislature, single executive body and one supreme judiciary. England, for example, is a unitary state. She has one parliament as her legislature, the King-in-Council as the executive and the judicial committee of the House of Lords as her supreme judiciary.
3. Written or unwritten Constitution:
A unitary government may or may not have a written constitution. As for example, England and France are unitary states. France has a written constitution but England has none
4. Rigid or Flexible Constitution:
Unlike a federation, a unitary state may or may not have a rigid constitution, e.g., the constitution of England is flexible but that of France is slightly rigid.
5. No Special Judiciary:
There is no need of having a special judiciary with wide powers of judicial veto in a unitary government. Even the highest court of U.K., for example, cannot sit in judgment over the law passed by Parliament.
1. Division of Powers:
In a federal government the powers of administration are divided between the centre and the units. The powers may be distributed in two different ways. Either the constitution states what powers the federal authority shall have, and leaves the remainder to the federating units, or it states what powers the federating units shall possess and leaves the remainder to the federal authority.
The remainder is generally known as residuary powers. The first method was employed in America and the second in Canada. The federal government in U.S.A., for example, is weak in relation to the states whereas the federal government in Canada is more powerful.
In a federation both the federal and state governments are independent and autonomous in the spheres of their powers. 'One is not subordinate to the other. Both derive their powers from the constitution which is the supreme law of the land. The powers enjoyed by the units are, therefore, original and not delegated by the centre.
2. Separate Government:
In a federal form of government both the centre and the units have their separate set of governmental apparatus. America is a federation of states. States have therefore separate legislatures and Separate executives.
3. Written Constitution:
A federal government must have a written constitution. As a federation is a political partnership of various states and consequently there must be a written agreement in the form of a written constitution.
4. Rigid Constitution:
The constitution of a federation should be more or less rigid. It is regarded as a sacred agreement, the spirit of which should not be easily violated. A flexible constitution allows a scope to the central government to curtail the autonomy of the federating states.
5. Special Judiciary:
In a federation, there are possibilities of constitutional disputes arising between the federal centre and the units or between one unit and another. All these disputes are to be adjudicated in the light of the constitution. For this purpose a special judiciary with wide powers must be established.
It should act as the custodian and guardian of the constitution. It should be vested with powers of declaring any law, national or local, ultra vires if it is at variance with the articles of the constitution. The constitution is thus the supreme law in a federation to which both the centric and the state must adhere to.