There are two aspects of sanction - legal and ethical.
Legal Sanctions: Legal Complaints should be dealt with in terms of the law, i.e. the Trade Marks Act or breach of contract.
The ASA's function is not to enforce the law, although it may advise people of their rights and obligations and the possible consequences of their actions.
Ethical Sanctions: The ASA in the case of precedent and/or the Committees may require the withholding of advertising space or time from advertisers. The ASA reserves the right to impose any other form of sanction warranted by particular circumstances.