A High Court judge has dismissed a claim by the family of barrister Mark Saunders that the investigation into his shooting by police is unlawful.

But Mr Justice Underhill said he was concerned about police officers involved in such cases conferring before recording their first account of the shooting.

He said this might well be unlawful and there was a danger that the opportunity for collusion could become institutionalised.

The judge gave permission to take the case to the Court of Appeal.

Mr Saunders died of multiple bullet wounds after a five-hour shoot-out with police at his luxury Chelsea flat.

The 32-year-old, who worked as a divorce lawyer, died after shooting at police officers, neighbours and buildings with a legally-owned shotgun from his £2.2 million Markham Square flat.

The judge was told at a hearing last month that the Independent Police Complaints Commission (IPCC) inquiry was flawed because officers involved in the shooting were allowed to confer before recording their accounts.

Tim Owen QC, representing Mr Saunders's sister Charlotte Saunders who brought the case, told the court the issue was whether this was compatible with human rights laws.

He said: "There can be no doubt that the present practice means that there is a substantial risk of collusion and of contamination. On the facts of the claimant's case, the risk is substantial.

"The officers were not separated before their accounts were obtained. The opportunity to confer, and therefore the risk of collusion, was increased by a number of events.

"There was a delay in providing initial statements. The Metropolitan Police Commissioner has now admitted that there was, in fact, conferring between the officers."

He said the IPCC had provided further opportunity to confer by organising meetings attended by groups of officers to put the questions to them.

Miss Saunders and her family, who believe the barrister was posing no further risk when he was shot, also sought a declaration from Mr Justice Underhill that there had been an unlawful failure to disclose sufficient information in the course of the investigation into the shooting on May 6.

This was also dismissed by the judge.

The IPCC practice of allowing officers to confer was agreed with the Association of Chief Police Officers (Acpo) and is contained in the Acpo Manual of Guidance on the Police Use of Firearms.

Acpo, the Commissioner of Police for the Metropolis and the Police Federation joined the proceedings as interested parties.

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