Undercover police units gathered and kept information on black justice groups that "served no purpose in preventing crime", a report will say.
Derbyshire Chief Constable Mick Creedon, who leads the report into the conduct of Scotland Yard moles which will be released today, will say the highly secretive Special Demonstration Squad (SDS), Special Branch and senior management flouted rules about what details should be kept.
A series of allegations were made against the SDS, including officers tricking women into serious sexual relationships and using identities of dead children without permission, which led to this inquiry.
The squad was also accused of infiltrating campaign groups of murder victim Stephen Lawrence and gathering information to "smear" his relatives.
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