Prerogative of mercy
Section 212(1)(a) · 1999 Constitution (2004 edition)
What Constitution says
(a) Grant any person concerned with or convicted of any offence created by any law of a state a pardon, either free or subject to lawful conditions;
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 94–95. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections