Ar hyn o bryd, mae rhieni'n cael defnyddio amddiffyniad cosb resymol yn erbyn cyhuddiad o ymosodiad cyffredin, ond nid yn erbyn cyhuddiadau mwy difrifol, er enghraifft, cyhuddiad o wir niwed corfforol.
Parents are currently able to use the defence of reasonable punishment against a charge of common assault, but not against more serious charges of, for example, actual bodily harm.