Former MP and Wanganui Mayor Michael Laws has launched a tirade against 3 News presenters Hilary Barry and John Campbell on social media.

Laws, a former RadioLive talkback host, wrote a Facebook post criticising Barry for being "utterly unprofessional" after she broke down on Thursday night following a story about Campbell.

He labelled her an "overpaid news presenter" in need of perspective, saying she was wrong to tear up over Campbell's departure.

"Compassion is for people who, through no fault of their own, suffer great loss or tragedy. It is not for people who decline a $1.2m contract and 3 years employ because they don't like an executive decision of their employers," he wrote.


Laws suggested her tears were an act of "mawkish sentimentality".

"Such so called compassion was absent on a raft of stories that had real tragedy. This was and never will be a tragedy," he wrote.

"I have no 'heart' for people who misuse news services for personal upsets: utterly unprofessional and in this case utterly undeserved considering he resigned over an ego issue.

"Child murders are a tragedy, innocent people maimed is a tragedy, hundreds made redundant is a tragedy.

"Sobbing over someone being offered another job on the same salary is pathetic, not sympathetic."

Laws' Facebook post has since been deleted.

Barry Tweeted her thanks to supporters for sending messages following Thursday night's broadcast.