The family of Jean Charles de Menezes - who was shot dead by officers who mistook him for a suicide bomber in 2005 - are considering legal action against Scotland Yard after it was claimed the force spied on them.
Scotland Yard is embroiled in a fresh scandal after claims officers gathered information about several grieving families involved in justice groups, including relatives of Mr de Menezes.
It is also alleged the force collected data on relatives of Cherry Groce, whose death sparked the Brixton riots, and Ricky Reel who died in mysterious circumstances in 1997.
The latest report on the force's secretive Special Demonstration Squad (SDS) will be published today. The unit, Special Branch and senior management at the Metropolitan Police are set for criticism.
Derbyshire Chief Constable Mick Creedon, who is leading the inquiry, will say that rules were flouted over what information should have been kept on record.
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