De minimis principle

Riverstone v Blacktown CC [2015] NSWLEC 137

We all know de minimis8, but how does it apply in practice?  First, it is a principle of construction, not a rule of law.  Second, its application always depends on text, purpose and context9.  Third, it inevitably involves a substantial element of value judgment10

In this case, development consent for works was refused as the council was not satisfied the works would ‘not increase flood levels on adjoining properties …’  The fact that floods may be ‘very small to very large’ went against de minimis applying.  It was not self-evident, said the court (at [23]), that the flood increase requirement should be read as qualified by a ‘trivial or minor’ breach.

This case is from Episode 33 of interpretationNOW!


8 Minor variations from a legal requirement are to be disregarded.

9 Farnell (1996) 142 ALR 322 (at 324-327), Unisys [1997] FCA 777.

10 Pearce & Geddes (at [4.22]), Samuels (1985) 6 Statute Law Review 167.