Police usually have to leave the office to find offenders but occasionally the crime comes to them.
Scott David Munroe (48) was in front of the Dunedin Central station with a friend late on January 17 after drinking heavily.
The pair bickered, Senior Constable John Somerfield said, which escalated to a verbal tirade from the victim.
''He has been the subject of some very nasty name-calling, bullying in fact,'' defence counsel Andy Belcher said of his client.
Munroe lashed out, the Dunedin District Court heard yesterday, punching the man in the nose, causing it to bleed.
The victim made the short walk into the station, closely followed by the defendant.
Munroe pushed the man in the back and he fell in front of the public counter.
Despite the speedy intervention of police, the defendant was unrepentant.
He explained to officers he had been called a nasty name, had struck the man and would do so again if it happened again.
Munroe pleaded guilty to assault after police downgraded his charge at the Dunedin District Court yesterday.
Mr Belcher said the incident had not been isolated.
His client had earlier received text messages from an associate of the victim ''accusing him of the very worst kind of child abuse''.
The comments from the victim followed that theme.
''In his view that warranted the force that he used. That's clearly not the case as far as the law is concerned,'' Mr Belcher said.
He acknowledged Munroe had a lengthy criminal history but said he was stabilising his life.
Judge Michael Turner sentenced the defendant to six months' supervision.
