Cardiff Council has handed a councillor a four months suspension after an investigation by the Public Services Ombudsman for Wales.
Its standards and ethics hearing panel made the ruling in the case of independent councillor Neil McEvoy, who is also a member of the Welsh Assembly.
This arose from a dispute over statements made by Cllr McEvoy about the council’s children’s services.
The panel said it was “aware of Cllr McEvoy’s personal views in relation to Cardiff children services and the Ombudsman and the panel reiterated that should Cllr McEvoy have concerns, these need to be channelled through correct procedures”.
The Ombudsman had found that Cllr McEvoy’s conduct may have breached the council’s code of conduct and the panel decided that he had failed to show respect and consideration of others, had used bullying behaviour and had brought the authority into disrepute.
It imposed a four months suspension from the council, for which Cllr McEvoy has a 21-day period in which to appeal.
In a posting on his Facebook page, Cllr McEvoy said: “Been stitched-up again. I've allegedly broken the code for speaking up for a child that alleged abuse in a private care home.
“The system in Wales has to change and I will be appealing. People who are abused are always let down.”
The BBC has reported that police were called after a disturbance at the panel hearing.