Sarah was kidnapped in Clapham by servicing officer Waynes Couzens in 2021; her body was found in Kent after being raped and murdered.
Sadiq Khan is expected to tell a London Policing Board meeting that the actions of PC Wayne Couzens ‘haunt’ the city.
It’s as he announces reforms to restore trust.
Last week, campaigner Patsy Stevenson, who was arrested at a vigil after the killing, said she was ‘exhausted’ at hearing promises.