The parents of Italian children who commit violent crimes face the threat of crushing financial penalties following a landmark ruling by a judge in Milan.

The mothers and fathers of five teenage boys who repeatedly raped a young girl have been ordered to pay her compensation totalling €450,000 because of their failure to give their sons an "education in feelings and emotions". Judge Bianca La Monica awarded the damages against all the boys' natural parents, including those who had separated from their partners and no longer had custody of their sons.

Many details of the case have not been disclosed because of laws regarding the identity of rape victims and minors. But, according to the daily Corriere della Sera, the girl was forced to have sex on a number of occasions between 2001 and 2003.

The girl was 12 at the start of the period and the boys were two or three years older. In assessing damages, Judge La Monica took into account the psychological damage to the victim and the fact that after the rapes she had left school early, thereby curbing her future earning prospects.

In a written judgment, the judge said the defendants came from seemingly normal families. Yet they appeared to have no understanding of the gravity of what they had done. They had given evidence about the rapes in a way that was "aseptic", she said. They had employed "words that were not expressive of emotions, using for the girl terms that made it clear there had been no consideration for her person."

It was only when they had been pressed to think about the effect of their behaviour on the girl that they had shown "glimmers of awareness". The judge said this showed the accused had not been brought up "in a context of respect for the feelings, wishes and bodies of others". She said that, in their defence, the mothers and fathers of the boys had offered various examples of their supposedly good parenting.

They had told the court they made sure their sons came home by a certain time. They had testified that their children were brought up to be good Christians. And they provided evidence of having ensured the boys attended sex education classes at school. In some instances, the point had been made that a defendant had not shown any apparent interest in girls.

But none of this, said the judge, was as important as the fact that there was "no trace in the minors' behaviour of an upbringing that provided for entering into non-physical relationships with others."

On damages against parents no longer directly involved in the upbringing of their sons, she said law gave the non-custodial spouse not just the right, but the duty, to monitor the upbringing of a child.