Relations Between Union and States
(1) While a Proclamation of Emergency is in operation, Parliament may make laws on any State List matter (or GST) for all or part of India. (2) Such a law ceases to have effect six months after the Emergency ends (without affecting things already done under it).
During a declared national Emergency (Article 352), the normal Union-State division of legislative power is temporarily suspended - Parliament gains the power to legislate on ANY subject, including ones normally reserved exclusively for the states, for the duration of the Emergency plus a six-month wind-down period.
This is one of the most significant ways a national Emergency reshapes India's federal structure - during such a period, Parliament could, in principle, legislate directly on subjects like state police administration that it cannot normally touch.