The family of a young woman who killed herself have accused police of failing to properly investigate a disturbing DVD on assisted suicide found in her flat – and called for the case to be reopened.

Islington Gazette: The flats in Fortnam Road, Archway, where Demi livedThe flats in Fortnam Road, Archway, where Demi lived (Image: Archant)

But a High Court judge told Demi Williams’ bereaved father that the Metropolitan Police had fully met its duty to interrogate the 22-year-old’s tragic death and denied the bid for a new inquiry on Tuesday.

Speaking after the ruling, father Goodeson Williams said: “It is my belief that the Met Police have failed us as a family. We continue to believe that Demi’s death was suspicious and will do so until a full investigation has been carried out.”

Former Highbury Grove pupil Demi took her own life by inhaling helium gas at her council flat in Archway just days after being released from a mental health crisis house in March last year.

When Demi’s body was found the DVD - described as a “propaganda exercise for suicide” at an earlier inquest into her death - was in the player and the front door to her home was open.

Islington Gazette: The messy living room where Demi Williams' body was foundThe messy living room where Demi Williams' body was found (Image: Archant)

Demi’s family have unanswered questions about whether anyone else was involved in her death and the judge was told they gathered a stash of evidence from her flat that was never collected by police.

The family launched a judicial review bid in the hope of forcing the Met to carry out a new investigation.

Their barrister Una Morris said: “At the heart of this case we have a young, vulnerable, black woman who died, by perhaps an unusual method, in circumstances that we say would arouse suspicion in any person, and especially should have aroused the suspicion of police.”

Ms Morris read excerpts from the DVD in court and argued that publishing and supplying it may have been an offence under the Suicides Act 1961, and should have triggered a full criminal inquiry.

Islington Gazette: Demi in happier times: Her family paid tribute to a 'loving daughter'Demi in happier times: Her family paid tribute to a 'loving daughter' (Image: Supplied by family)

One excerpt said: “Passively observing suicide is not a crime.” Another: “While it’s advisable to have someone present, they need not be physically involved thus clear of legal risks.”

Ms Morris said: “It’s not in dispute that this was material that Miss Williams had access to and on this evidence alone it’s credible to suggest that somebody else may have been involved in her death.”

But Mr Justice Walker denied permission for a judicial review, saying police had carried out an “effective” inquiry into the circumstances of Demi’s death.

The decision upheld an earlier ruling by Mr Justice Lewis which found police had “seized evidence, interviewed witnesses and made door-to-door inquiries” and fully met their duties.

The family are in discussion with their legal team about whether to appeal the ruling.

Following an inquest into Demi’s death in December, a coroner made two reports to prevent future deaths – including one to the Crown Prosecution Service relating to the DVD.

Demi’s father has spoken previously of the pain of losing his “loving daughter” - saying Demi’s death “broke our hearts”.

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