We don't have synonyms for misdemeanours yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are misdemeanor, misdemeanour and misdemeanors.
(n) :
(British spelling) Alternative form of misdemeanor. [(law, criminology, historical in UK) A lesser criminal act in most common law legal systems, generally punished less severely than a felony.]
(n) :
(British spelling) Alternative form of misdemeanor. [(law, criminology, historical in UK) A lesser criminal act in most common law legal systems, generally punished less severely than a felony.]