How Were the 234 Constituencies of the Tamil Nadu Legislative Assembly Determined? – Background of the Delimitation Commission Decision

Introduction

The Tamil Nadu Legislative Assembly currently has 234 constituencies (Assembly Constituencies). How and when this number was determined is an important political and constitutional question. This structure was formed as a result of a decision taken by the Delimitation Commission after the 1961 Census.

1. Constitutional Basis

This arrangement is based on Article 170 of the Constitution of India.

Article 170 states that:
• Members of the State Legislative Assembly should be determined based on population
• Constituencies must be reorganized by the Delimitation Commission

In addition:
According to the Delimitation Commission Act, 1962 – Section 8(b),
the number of State Assembly constituencies must be an integral multiple of the Lok Sabha constituencies allotted to that state.

2. 1961 Census and Delimitation

After the 1961 Census, the Delimitation Commission (Chairman: Justice J. L. Kapur) carried out constituency reorganization.

At that time:
• Total Lok Sabha seats (States) = 481
• Madras State (present-day Tamil Nadu) = 41 Lok Sabha seats

Considering population changes:
Madras State's Lok Sabha seats were reduced from 41 → 39.

3. Method Used to Determine Assembly Constituencies

At that time, a general practice existed:
1 Lok Sabha constituency = 5 Assembly constituencies

If applied to Madras State:
39 × 5 = 195 Assembly seats

However, at that time the Madras Assembly had 206 members. Reducing it to 195 seats was considered to weaken public representation.

4. Important Decision of the Delimitation Commission

To resolve this issue, the Delimitation Commission made an important decision.

For Madras State alone, the Assembly multiple was increased from 5 to 6.

That means:
• Lok Sabha seats = 39
• Assembly multiple = 6

Therefore:
39 × 6 = 234 Assembly seats

As a result:
• The number of Assembly members did not decrease
• Instead, it increased to 234.

5. Why This Change Was Important

This decision had several important impacts:

• It protected democratic representation
• It maintained the efficiency of the Legislative Assembly
• It ensured balance in the state’s political structure

This arrangement has continued from 1963 until today.

6. Impact on Electoral Mathematics

In the Tamil Nadu Legislative Assembly:

• Total constituencies = 234
• Majority required to form the government = 118

Based on this:
• Coalition politics
• Election strategies
• Constituency-based political calculations are all shaped.

Conclusion

The 234-constituency structure of the Tamil Nadu Legislative Assembly was not an arbitrary decision. It was a structural decision taken by the Delimitation Commission in 1963 to protect democratic representation. This system has served as the foundation of the state's political structure for more than six decades.