The truth is every action has a risk/ potential risk/consequence or a potential consequence.
A potential consequence of having an affair with a married person,, is getting beat up or having other nasty things happen to you.
A risk or consequence of beating someone up, is getting jail time, loosing your job and a criminal record.
FWIW, I see job DBS disclosures and the criminal records associated with them. If a person described how the record happened, I/we would look as whether she had committed any other crime and depending on that, it would not automatically prevent her from getting a job working with children.
A naughty kid, is not a comparison to your husband's mistress and we use a common sense approach, bearing in mind the rehabilitation of offender's act. Much depends on how long ago it was and I would not class this as your bog standard violent person, noting the mitigating circumstances.