Susan Nicholson death: Fresh inquest appeal over police murder probe

There were similarities between the cases of Caroline Devlin (left) and Susan Nicholson, the trial of their killer Robert Trigg was told

The family of a woman murdered by a double killer have appealed to the High Court for a full inquest into police "failings" in the case.

Susan Nicholson was killed by Robert Trigg in 2011, five years after he had killed his previous partner, Caroline Devlin, in similar circumstances.

Neither deaths were initially deemed as suspicious by Sussex Police.

Ms Nicholson's parents are challenging the senior West Sussex coroner over the scope of a new inquest.

Trigg, 54, was jailed for life in 2017 for the murder of Ms Nicholson and manslaughter of Ms Devlin at their homes in Worthing, West Sussex.

Following the conviction, the High Court quashed the findings of accidental death in the original inquest into Ms Nicholson's death and ordered a new one.

The senior coroner for West Sussex ruled it would be a short inquest, with no witnesses questioned.

Her parents, Elizabeth and Peter Skelton, want the new inquest to investigate if police failed to adequately protect their daughter.

They argue that there should be a full inquest under Article Two - the right to life - of the Human Rights Act, which can scrutinise the role of public bodies in a person's death.

Mr Skelton said before the hearing: "I see this hearing as an opportunity to make sure that there is a proper inquiry into whether Susan's death could have been prevented."

Robert Trigg behaved in similar ways after killing both his partners in similar ways, his trial heard

In a written submission to the High Court, Heather Williams QC said the coroner's decision was unlawful as it was "plainly arguable" that Sussex Police had breached its duties to protect Ms Nicholson and to effectively investigate the death Ms Devlin.

Officers had been called to Ms Nicholson's flat six times in the weeks before her death over reports of violence, and one of his former partners was taken to hospital after he attacked her.

But the force did not find the similarities between the cases suspicious and treated Trigg as a bereaved partner rather than a suspect.

At least two police officers were involved in the investigations into both women's deaths and were aware of his connection to the cases.

In 2011, coroner Michael Kendall ruled Ms Nicholson had died accidentally after Trigg claimed he rolled on top of her unintentionally while they slept on a sofa.

It was only after Ms Nicholson's parents hired professionals to re-examine the original pathologist's report that the case went to court.

Sussex Police said the appeal should be dismissed, while the senior coroner is remaining neutral on the challenge.

The inquest appeal is expected to last for three days.

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