Minor offence or transgression (12)
I believe the answer is:
misdemeanour
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">minor offence</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">transgression</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that misdemeanour is a type of offence)</span><br/ ><br/ ></span>
(Other definitions for misdemeanour that I've seen before include "Minor wrongdoing" , "Minor violation" , "Minor offence" .)