asked Her Majesty's Government:
Further to the replies by the Lord Drayson on 9 January (Official Report, cols. 4–6), whether the exercise of the Royal prerogative to pardon an offender requires the existence of a legal basis; and, if so, what law provides that legal basis.
Pardons are part of the Royal prerogative of mercy, which is part of the common law. The criteria for granting pardons are set by the Crown, may be altered and are not, therefore, enshrined in law. This permits flexibility but the prerogative should not be wielded arbitrarily, not least because its use by the executive affects judicial decisions. For this reason, it is exercised according to established principles, developed through the policy and practice of the Home Office. This provides a degree of certainty consistent with the rule of law.