The parents of Jaycee Lee Dugard must be overjoyed that their long-lost daughter has been found.

However, the focus is now on the two people who allegedly abducted and sexually molested her over the 11 years of her disappearance -- Phillip Garrido and his wife Nancy. She too is charged with sexually assaulting Jaycee.

Of course it is not possible for anybody to determine at this point if Nancy Garrido is guilty as charged but the mere fact of such a charge is shocking and stunning the world.

Women are not thought of as sexually voracious, at least where children are concerned. The image of a paedophile is of an isolated, usually single man who lures his prey unsuspectingly into his dark and evil world. Just as the Victorians could not even consider the possibility of women being attracted to their own sex (and so lesbianism was never criminalised), modern society finds it almost impossible to consider the prospect of female child abusers and so discussion of the abuse of children by women may be one of the last taboos in our society.

The universal image of women as maternal and nurturing, Madonna-like and gentle, is so ingrained that the thought of them as sexually avaricious where children are concerned is repellent. Yet most psychiatrists will have a few patients who report sexual abuse by an an older female, sometimes a babysitter, sometimes a teacher but at times by their mother. This, the sexual violation by a mother, is horrifying and incomprehensible.

Yet history, including our own here in Ireland, has shown that women can at times be complicit or even dominant in the sexual abuse of others. Myra Hindley, Rosemary West, and the woman in the 'Roscommon case' earlier this year all involved females in the direct sexual abuse of children. Not forgetting the soldier Lynndie England, who became the face of Abu Ghraib prison for her abuse of male prisoners.

Victims

Because it is not spoken about, there is little information on how commonly sexual abuse by females occurs or on the profile of those involved. One study, now over 20 years old, suggests that about 15pc of male victims and five per cent of female victims were abused by women, while another study reports that among the totality of sexual predators, 25pc are said to be women.

However other studies, that are based on self-report rather than on documented legal information, put the proportion abused by females as much higher and on a par with the figure for males. There is conflicting information on the proportion involving a co-perpetrator.

Most female abusers have serious emotional problems, including difficulties with mature relationships, dependence on their partners and substance misuse. Contrary to earlier views, only a minority is psychotic.

Similar to the disbelief that priests and brothers could perpetrate abuse, it is recorded that up to 80pc of victims of female abusers are not believed. There is also evidence from research that in the backgrounds of rapists and sexually aggressive men there is an alarmingly high rate of alleged abuse by females, with figures of between 60-80pc being cited.

There is little information as to what motivates such behaviour in women, but some studies are emerging and show that those with co-perpetrators may be excessively dependent and act not primarily from their own motivation but under the influence of their partner.

Those acting independently may see their child, often an older son, as a mate and he becomes unwittingly cast in the spousal role. Others, particularly those abusing daughters, see the child as an extension of themselves. Many will themselves have been victims of sexual abuse and many have sexual identity problems.

Undoubtedly the case of Jaycee Lee Dugard, whatever the outcome, will generate much more discussion about the role of women in circumstances such as these. For most ordinary people, unaware of such evil in the world, another nail has been inserted in the coffin of innocence and our hallowed beliefs about motherhood and goodness have been challenged.

- Patricia Casey