What kind of people kill their children?

Search the Supreme Court archives. There is Ravindra Verma of Rosy Colony in Ghaziabad who battered his five children to death with a silbatta, after fighting with his wife. In 2013, the Court's verdict was a death sentence for this "rarest of rare" crime. He is not alone. Many men are waiting on the nation's death row for filicide, or the murder of one's own child. But it's hard to find a mother there. "It's a very rare crime. Not just in India but across the world," says Dr Manju Mehta, former head of child psychology at the All India Institute of Medical Sciences, Delhi.

It's not as if we haven't heard of controversial cases involving mothers: There is the 2008 Aarushi Talwar case. There is also the Nirupama Pathak murder case of 2010, where Sudha Pathak has been under scrutiny for the death of the 23-year-old journalist at her Jhumri Telaiya home in Jharkhand. In both cases, investigations remain inconclusive.

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Across the world, it's a crime that baffles psychiatrists. Since the 1950s, there have been attempts to understand motivation for killing one's own child. According to psychiatrist Aniruddha Deb of Kolkata, these could be varied: from "honour killing" to extreme selfishness: "Say, the possibility that a child can create difficulty in the mother's own future. Or she can benefit from the death of a child in some way".

The most accepted analysis comes from American forensic psychiatrist Phillip Resnick. According to him there are usually five reasons behind a mother killing her child: when they think that it is actually in the best interest of the child; when they are suffering severe psychiatric issues-depression to schizophrenia; when a child is regarded as a hindrance; when it is accidental and unintentional; when it is a revenge upon the spouse. To all these, recent research adds "fear of social stigma" - say, for having a child outside of marriage.

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"Most mothers who kill their children usually have mental illness, chronic depression, extreme personal problems, unexpressed anger, intense frustration and stress in their lives," says Mehta. "Perhaps, somebody felt very inadequate as a parent, was under constant criticism for long. And then reached a breaking point. Typically, a triggers, the final straw, tips them off the edge."

Usually, women who kill with a purpose tend to be older. With some kind of loss they suddenly change from being devoted a mother to a murderer - usually using violent methods like knives or guns. Those who kill by neglect or accidentally, tend to be younger, from lower socioeconomic background and take to strangulation or smothering.

What else? Many such women have borderline personality disorders, say psychiatrists, completely unable to control their rapid mood shifts, constant emotional swings between inappropriate intense rage and sadness, unstable relationships, erratic self-image and acute fear of abandonment.

It's a dark, dark world - whichever way you look at it.

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