The investigation, code-named Operation Russell, allegedly raised questions about former commander Ray Adams's conduct before the Lawrence case, the Guardian said.
There was reportedly insufficient evidence to bring criminal charges and Adams told the newspaper this exonerates him and denied any wrongdoing.
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The live stage version of Peter Kay's Phoenix Nights has reportedly been cancelled after actor Ted Robbins collapsed on opening night.
The much-loved local character, who had lived on the city's streets for decades, died in hospital this week after falling ill.
Man City remain five points behind Chelsea in the Premier League title race after a 1-1 draw at Stamford Bridge