Firing ten men, sacked for violation of rule (12)
I believe the answer is:
infringement
'violation of rule' is the definition.
(infringement or contravention of a rule)
'firing ten men sacked' is the wordplay.
'sacked' is an anagram indicator.
'firing'+'ten'+'men'='firingtenmen'
'firingtenmen' is an anagram of 'INFRINGEMENT'.
'for' acts as a link.
(Other definitions for infringement that I've seen before include "Minor lawbreaking" , "Violation of law" , "Offence" , "Breaking (of a law, etc)" .)