Police traipsed through 46 Lower Belgrave St on the night of Sandra Rivett’s murder, but did they contaminate the evidence?
The police files are still closed. Where there have been unanswered questions, enticing myths and conspiracies have filled the void.
Alex von Tunzelmann pieces together what we can know of the investigation, trying to separate fact from fiction.
She hears from two policemen who worked on the Lucan case and reassesses the forensics with an ex-Metropolitan Police detective.
Stories emerge about close relations between the press and police and she wonders if booze, bribes and class deference may have obscured the truth.
Producer: Sarah Bowen