A 12th person has been arrested as part of an investigation into alleged police corruption in Westminster .
The 40-year-old man from Kingston was detained in south-west London on Wednesday (March 9) on suspicion of bribery.
The man, who is not a police officer, has been bailed to return in late June pending further enquiries.
The Met is investigating allegations of corruption by police licensing officers in Westminster and inappropriate relationships between police officers and local business people.
Eleven people - including three police officers - have previously been arrested as part of Operation Joseph and all remain on bail.
Previous arrests
A police sergeant and a constable were among six people arrested last June on suspicion of conspiracy to commit misconduct in public office. They were both suspended.
A 30-year-old male PC also based in Westminster was arrested last September on suspicion of the same offence. He remains on bail and has been placed on restricted duties.
A fourth police officer - a 43-year old female PC based in Westminster - was interviewed under caution last August but the investigation into her is complete and she is no longer subject to restricted duties.
The investigation is being carried out by the Met's Directorate of Professional Standards Anti-Corruption Command.
