Image caption Michael Atherton, 42, killed his wife, her sister and niece before killing himself

In the last three months, three fathers have killed their partners, children and themselves - but what drives men to take such drastic action? Radio 4's File on 4 investigates.

"He walked out of the house, took a shotgun from the car, picked our family out and shot them."

Within a matter of minutes taxi driverMichael Atherton killed his partner Susan McGoldrick, her sister and her niece - before finally turning the gun on himself.

For Susan's family it was a loss from which they will never recover. But this family is not alone.

There's this notion that if they feel they can't carry on in this world they're not going to leave other people behind Dr Marilyn Gregory, Sheffield University

The tragedy was one of three so-called "family annihilations" in as many weeks - and there are around five such incidents per year in England and Wales.

Despite this, little research has been done to find out what makes men "snap" with such devastating consequences - and if anything can be done to prevent it.

The term "family annihilation" was coined in the United States - in the UK it remains a crime without a name and does not feature in its own category in official crime figures.

It is only by piecing together details of murder and suicide cases that anyone can estimate as to how often it is happening. According to a study by academics at Manchester University there were 39 cases between 1996 and 2005 in England and Wales.

Experts say the vast majority of these cases involve men - while there have been some involving women, they are very rare by comparison.

Domestic violence clue

Dr Marilyn Gregory at Sheffield University has examined 20 cases in Yorkshire and Humberside.

Image caption Susan McGoldrick, Alison Turnbull and Tanya Turnbull died of shotgun wounds

She told Radio 4'sFile on 4programme that tragedies like this happen with "monotonous regularity", with those involved feeling an overpowering need to stay in control at all cost.

"They are men who have a lot invested in life. They have been able to achieve masculinity in positive ways.

"They've been working, having a relationship, they've been fathers."

However, the breakdown of such relationships can lead to a tragic chain of events.

"When the woman says she's leaving, then the man is shattered. He feels he's losing control over everything in his life.

"There's this notion that if they feel they can't carry on in this world they're not going to leave other people behind."

Dr Gregory says domestic violence can be one of the early warning signs.

This rings true with Susan McGoldrick's family who say it was her husband's violence and threats towards her and her daughter which prompted Susan to say she wanted to end their relationship.

Susan's brother, Norman Hardman, told File on 4: "I have come to the conclusion he may have planned it. I believe he thought to himself 'If I can't have you, nobody else will.'

Michael Atherton had a gun licence but in 2008 his guns were confiscated by Durham Police after he threatened to kill himself and Susan. The decision was later overturned and they were given back.

Researchers in Munich are building the firstdatabaseof family 'homicide followed by suicide' in seven European countries. The data suggests the availability of guns has an impact on the incidence of this type of crime.

England and Wales have a low rate of family murders compared to countries such as Switzerland, Finland and Germany, where gun ownership is higher.

Family debt crisis

In 2008 businessmanChris Foster shot his wife and daughter, Kirstie,with a legally held gun before setting fire to his £1m mansion in Shropshire, killing himself.

Image caption Chris Foster shot his wife and daughter before setting fire to his home and killing himself in 2008

Andrew Foster says he believes his brother Chris - who had severe financial problems at the time - had a twisted idea he was saving his family from the shame of financial ruin and public humiliation.

"He was in a financial crisis - and his personal life was in crisis too. He didn't want Jill and Kirstie to be left with no home and no money."

Evidence from the US suggests a personal financial crisis could be a leading cause in other cases, too.

When the economy sours, family murders increase...when someone loses his job, he feels life is not worth living Prof Jack Levin, Northeastern University

Jack Levin, professor of sociology and criminology at Northeastern University in Boston, has looked at the number of cases that occurred during the recession in 2008. He found that as the unemployment rate increased so did the number of family massacres.

"When the economy sours, family murders increase... when someone loses his job, he feels life is not worth living," explains Prof Levin.

"But as a breadwinner, as someone who's always felt responsible for the well-being of the children and spouse, he kills them all in order to reunite later on in a spiritual sense."

Suicide in middle-aged men remains high on the agenda and Samaritans urge anyone to talk to someone if they are worried about their relationship, losing their job, or debt problems.

Experts like Prof Jack Levin say that is all that practically can be done.

"If a man feels he has no place to turn, although you can't be sure he is going to commit a family massacre, you can be sure he needs your help."

Forensic psychiatrist Dr Kevin Murray from Broadmoor secure hospital believes this is a subject which demands much more research.

"Lots of families have problems. Knowing which one will turn out to be a tragedy is well beyond our current knowledge base."

Listen to the full report onFile on 4onBBC Radio 4on Tuesday, 6 March at 20:00 GMT and Sunday 11 March at 17:00 GMT.Listen againvia theRadio 4 websiteor download thepodcast.