David Odunuga stabbed Brian Edwards three times near Finsbury Park in September 2023.
All four will be sentenced at Kingston Crown Court on 7, June 2024.
A number of children were safeguarded as a result of the officers’ work.
Detectives investigating a fatal collision are appealing for anyone with information or footage to come forward.
A man who absconded from a mental health facility in east London has been found.