Dame Cressida Dick has been referred to the police watchdog after publicly supporting a senior officer who faces a criminal trial in relation to a bullying probe.
The Commissioner of the Metropolitan Police defended Matt Horne, Deputy Assistant Commissioner of the Force in evidence to MPs earlier this year.
Mr Horne was found guilty of three counts of misconduct while deputy chief constable of Essex Police before taking his role at the Met in 2019.
On Friday, the London Mayor's Office for Policing and Crime (Mopac) said it had referred a complaint about comments made by Dame Cressida to the Independent Office for Police Conduct. The Telegraph reported the complaint was made over her public comments about Mr Horne.
In evidence to the Home Affairs Select Committee at a hearing in May, Dame Cressida said she made the decision to appoint Mr Horne as head of professional standards with her “eyes absolutely open.”
“I stand by it and I stand by him,” she added.
The Met police chief has been embroiled in several high-profile controversies this year and is currently awaiting a decision from Priti Patel, the home secretary, on whether or not to extend her contract, which expires in April.
She faced calls to resign in March after the Met's response to a vigil held over the killing of Sarah Everard, which was seen as heavy-handed by many.
In June, the force was labelled “institutionally corrupt” after a probe into the unsolved murder of private detective Daniel Morgan. Dame Cressida was accused of delaying the probe and the force was said to have prioritised protecting itself and its officers when faced with corruption claims.
The Met again faced criticism last month over its handling of public order during the chaos of the Euro 2020 finals, when crowds of ticketless fans stormed Wembley stadium while officers were on guard to support security staff.
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