"The details of the commission of the offence are the
essential facts that will afford the primary basis of the
court's sentence. They will show the nature of the actions
by which this particular offence was committed. Such facts
may well be the same as those that would be embraced under
the Victorian formula. For example, it seems obvious that
in a case of unlawful carnal knowledge, the critical
details may well include facts that would show it to be a
case of seduction by a step-father of a minor as distinct
from consenting parties of similar age. In a drug
possession case, they will include details such as at least
the approximate quantity of the drug, and may if
sufficiently relevant, include the purpose of the
possession. Criteria cannot effectively be laid down in
advance for particular offences, because a factor which may
have a dramatic bearing on one case will be of little
importance in another. There may of course be some facts
(such as alleged good character, work record and the like)
as to which the prisoner bears an evidentiary and
persuasive onus. The essential practical guidance appears
in R v Welsh 'a trial judge would necessarily be guided or
influenced in his acceptance or rejection of particular
facts by having regard to the significance of their bearing
upon the increasing or reducing of what might be considered
an average or normal sentence (cf Briginshaw v Briginshaw
[1938] HCA 34; (1938) 60 CLR 336).' (R v Welsh at 595.)
It is therefore possible to see the whole proceeding as
covered by the single sliding scale recognised in
Briginshaw. At the lower end of the scale, most
antecedents would need to be proved only on the balance of
probabilities. At the higher end of the scale the details
of the offence itself will need to be established beyond
reasonable doubt. In between these extremes the necessary
degree of satisfaction will vary according to the gravity
of the fact to be proved and its potential effect upon the
prisoner."