no harm, no foul
Definition from Wiktionary, the free dictionary
- Encapsulation of the idea that although technically a breach of some code or law may have occurred there is no need for punishment, apology or retribution if no actual damage occurred.
- He parked in my space but as I was away at the time: no harm, no foul.
See also 
- the ends justify the means
- de minimis non curat lex (“the law will not cure (or concern itself with) trifles”), de minimis
Usage notes 
Phrases with the same construction are common and productive. See the related terms below.
Related terms 
- ^ Bryan A. Garner (editor-in-chief), Black's Law Dictionary, Seventh Edition, West (publisher, 1999), page 443.