It is to be used in case any substantial constitutional question of law is involved, or gross injustice has been done.
[2] Any aggrieved party can file SLP against the judgment or order of refusal of grant of certificate.
This petition is required to state all the facts that are necessary to enable the court to determine whether SLP ought to be granted or not.
The Supreme Court of India may also refuse to grant the leave to appeal by exercising its discretion.
There is catena of judgments mentioning about the scope of power of Supreme Court under Article 136, the maintainability of special leave petitions.