"To permit deliberation on the subject at the next Plenary Council [of the CSM], it was decided, by decree issued today by the vice-president of the Council, to start an inquiry," the CSM said in a statement sent to the media.

The CSM is the independent body that has disciplinary authority over Portugal's judges and magistrates.

The debate centres on a ruling at Porto's appeal court, dated 11 October, in which the judge who drafted the text, Neto de Moura, expresses moral censure of a woman resident in Felgueiras who had been a victim of domestic violence, playing down the seriousness of the crime on the grounds that she had committed adultery.

The judge cited the Bible, the Portuguese penal code of 1886 and also other civilisations that punish adultery with death in playing down the violence exercised on the women by her husband and her lover - who were both given suspended sentences by a lower court.

"Adultery by the woman is a conduct that society has always condemned and condemns strongly (and honest woman are the first to stigmatise adulterous [ones]) and for this reason the violence exercised by the betrayed, angered and humiliated man is seen with some comprehension," reads the appeal court ruling, which was also signed by the other senior judge in the case, Maria Luísa Abrantes.

Earlier on Wednesday the CSM had said that it would review and respond to the complaints it had received against the ruling, but also said that so far "no proceedings of a disciplinary nature" had been started against Neto de Moura.

The Portuguese Association of Woman Justices, the Portuguese Victim Support Association and women's rights organisations have all expressed outrage at the ruling.

A petition calling on the CSM to take a stand on the issue and for an "urgent and serious reflection" on the need to change the system under which judges are assessed "so that cases like this are avoided in future" has also been signed by more than 5,000 people.

Portugal's president, Marcelo Rebelo de Sousa, without directly referring to the case in question, told journalists in the Azores that in Portugal it is the 1976 Constitution and the laws in force under it that apply, and that the holders of all public offices should observe and enforce these and no others.