The Parliament can legislate on a subject in the State list - (1) by the wish of the President (2) if the Rajya Sabha passes such a resolution (3) under any circumstances (4) by asking the legislature of the concerned state
(2) if the Rajya Sabha passes such a resolution Explanation: If the Rajya Sabha passes any of the subjects of the state list with 2/3 majority of the House, declaring the subjects to have national importance then According to Art. 249 of the Constitution parliament acquire the power to make laws.