According to Black, we can quantify the occurrence of
law in a given context and can measure its shifts and
changes as a product of other changes in society. The
quantity of law changes, it increases and decreases, it
varies by time, and it is very much a product of changing
social trends. We can look to external cues to access the
precursors of policy adoption. Each time we enact,
initiate, invoke, apply or enforce the law, we put the law
into action (Black, 1976). For example, Black proposes
that as social inequality increases, law will also increase.
Black suggests that examination of the forces that shape
public policy requires being cognizant of not only the
decisions of individual policymakers, but additional
societal influences. By measuring the law in action, we
are able to quantify the occurrence of law, and of any
factors that might influence law in a particular society.
Treating legal change quantitatively represents an
under-researched approach to understanding variation
in law and thus helps to extend theories of law making
(Hays & Glick, 1997). Modelling indicators on the
adoption of municipal smoking bylaws in Canada, in
addition to explaining the trend in bylaw adoption,
builds upon legal theory by emphasizing the role of
multiple policy inputs on shaping legal change.