Q. When parliament can legislate matters in the State List?
Answer: If Rajya Sabha passes a resolution by 2/3rd majority
Notes: Article 249 of the Constitution, if the Rajya Sabha passes any of the subjects of the state list with 2/3 majority of the present and eligible voters of the House, declaring the subjects to have national importance, on that subject parliament acquires the power to legislate i.e. to make laws.