Julia Pemberton: Police delayed entering the house
The killing of Julia Pemberton and her son Will in November 2003 should not have happened.
They were shot dead by her estranged husband Alan at their home in Berkshire, after a year of repeatedly begging the police for help.
He then killed himself. Her extended family, from Swindon, were grief-stricken.
Support for sufferers
But from that tragedy has grown a determination and resolve to help stop others suffering similarly.
And they will take their campaign further when they go to the High Court. Julia's brother Frank Mullane has never done anything like it.
Frank Mullane addressed the Amnesty International Conference
At home in Wiltshire he extensively researched domestic violence, learning about the laws that deal with it, talking to those who have suffered from it.
"You have to tap into loads of other families," he says. "There are lots of people out there, academics, MPs, who are interested and want to help you lend influence towards change."
He has given numerous newspaper, radio and television interviews.
Frank Mullane: An incisive analysis of the law. Poonam Joshi
He has made well-received speeches to organisations ranging from the police to Amnesty International.
"He is someone who has taken a great personal tragedy, but is using it to try to protect the rights of others," says Pooman Joshi of Amnesty.
"He probably never saw himself as a human rights defender, but he has a very incisive analysis of where the law has gone wrong."
South Swindon MP Anne Snelgrove is supportive
Early on the family enlisted the help of their MP. South Swindon's Anne Snelgrove went on to raise the case in Parliament.
"Julia Pemberton's family have fought extremely hard, and I pay tribute to them.
"They have been awarded an homicide review and now they're fighting to make sure it will be fair."
Their case broke new legal ground: the law which introduces reviews for such killings is only just taking effect.
But Frank Mullane will not rest yet. He believes the scope of the review is too limited, and the part played by police must be critically examined.
"I find it extraordinary that for such a prevalent crime in this country police officers are not mandatorily trained," he says.
"This has to go all the way up, not just for front line officers; it has to go to senior officers."
It is nearly three years since his sister and nephew were killed. The latest legal battle may take months to resolve.
But it will not diminish the family's determination to prevent similar tragedies happening again.
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