"Complaints such as assault, verbal abuse or suspected theft by the driver should be*reported to*Sussex Police*as soon as possible for an investigation."
https://www.brighton-hove.gov.uk/content/parking-and-travel/travel-transport-and-road-safety/hackney-carriage-office-taxi-complaints
So how many cloned false identities has he got now.
I wouldn't have thought that taking someone else's passport was legal. Could be interesting next time he tries to through immigration at the airport.