Population control and family planning is listed under which List of the…

The Constitution divides legislative subjects between the Union and the States through the Seventh Schedule under Article 246: List I (Union List) is for Parliament alone, List II (State List) is for the state legislatures alone, and List III (Concurrent List) lets both legislate on the same subject (with the Union law prevailing on a conflict, Article 254). Any subject named in none of the three lists falls to Parliament's residuary power under Article 248.

"Population control and family planning" was not part of any list when the Constitution was adopted in 1950. The Constitution (Forty-second Amendment) Act, 1976 inserted it as an altogether new Entry 20A of List III -- the Concurrent List -- so both Parliament and every state legislature can legislate on it, which is exactly why the Union's national population policy and the states' family-planning programmes operate side by side.

• Union List -- reserved exclusively for Parliament (e.g. defence, foreign affairs); population control and family planning is not confined to Parliament alone, since the entry inserted by the 42nd Amendment lets the states legislate on it too.

• State List -- population control and family planning was never a distinct entry here to begin with; the 42nd Amendment Act, 1976 created it as an altogether new item directly in List III, so it was never part of, or removed from, the State List.

• Residual subjects -- these are matters named in none of the three lists (Article 248); this subject is expressly numbered as Entry 20A, so it cannot be residuary.

Hence, population control and family planning is listed in the Concurrent List (List III).