Parsimony
A sentence should not be greater than what is necessary to achieve defined social purposes.
▫“the court should lean towards mercy. We ought not award the maximum which the offence will warrant, but rather the minimum which is consistent with a due regard for public interest.” Webb v O’Sullivan [1952] SASR 65 at 66.
But note that there is some disagreement as to the operation of this principle: See eg. Blundell v The Queen (2008) NSWLR 660.