No misconduct charges for senior official Jennifer Izekor
The commissioner of the former police watchdog will not have misconduct charges brought against her, the Crown Prosecution Service (CPS) has said.
Jennifer Izekor was being investigated over her handling of assault and racism claims against three policemen.
The case involved an off-duty firefighter who was Tasered in Harrow a month after the London riots in 2011.
However, Police Scotland is still investigating the allegations against Ms Izekor.
Ms Izekor left the Independent Police Complaints Commission (IPCC) in January 2018 when it was re-launched as the Independent Office for Police Conduct (IOPC).
Three officers from the Metropolitan Police - who were cleared at a disciplinary hearing in 2016 - claimed evidence had been suppressed and lodged a criminal complaint against the conduct of the IPCC.
She always denied any wrongdoing.
In December, following an extensive inquiry, Police Scotland provided a report to the CPS containing more than 700 documents.
After examining the material, senior specialist prosecutor Sarah Ingram said there was "insufficient evidence" to establish that Ms Izekor had "wilfully neglected" to perform her duty or "wilfully misconducted" herself.
The CPS also declined to bring charges against an IOPC investigator who was suspended during the inquiry.
A letter from Ms Ingram, seen by BBC News, noted that even though the Police Scotland investigation might continue there was "unlikely" to be any further evidence that would affect her decision not to bring charges.
A CPS spokesperson said: "Police Scotland submitted a file of evidence to the CPS in December regarding allegations of criminal conduct by officials investigating police officers from the Metropolitan Police.
"Having carefully reviewed the available evidence we have concluded the case does not meet the evidential test and the CPS will be taking no further action."