The Post Office Investigation Branch

Who were the investigators in The Great Train Robbery?

Our temporary exhibition, ‘The Great Train Robbery: Crime and The Post’ uncovered the work of the Post Office Investigation Branch in solving this famous 1960s crime.

What was the Investigation Branch?

The Post Office Investigation Branch (IB) is the oldest recognised criminal investigations force in the world. For more than 335 years it has worked to detect offences against the post and prosecute the perpetrators of these crimes.

The work of the Investigation Branch is currently under scrutiny following the revelations of its role in miscarriages of justice against innocent postal workers. This blog article looks at the historical role the Investigation Branch played in The Great Train Robbery.

The Post Office Investigation Department Logo on a plaque © The Postal Museum

The work of the Investigation Branch

Post Office Investigators undergo intensive training, including interview techniques, preservation of evidence and preparation of cases for consideration by the prosecuting authority. The unit includes crime prevention surveyors who carry out inspections of postal premises and security operations, as well as information systems analysts who monitor patterns of crime.

The Latin motto of the Post Office Investigation Department was:

‘Suaviter in Modo, Fortiter in Re’ – meaning ‘Gentle in Manner, Resolute in Deed.’

Investigator’s Hard Hat designed to protect the wearer during potential attacks, c1950

As well as alleged crimes by the public, the unit also investigates alleged offences by postal staff. In some cases, this work has involved investigators going undercover.

Investigating the ‘Crime of the Century’

In the 1960s Post Office Investigators worked in collaboration with the police to solve The Great Train Robbery, in which a gang led by Bruce Reynolds stole £2.6 million from a Royal Mail train travelling from Glasgow to London.

Page one of the report by Richard Yates, Assistant Controller of IB (POST 120/95)

A Senior IB Officer was sent to the scene of the crime and all other IB officers engaged on the Mail Bag Section ‘presented themselves for duty’ at Post Office HQ on St. Martin’s Le Grand in Central London.

Reporting for duty at Post Office HQ IB Investigator Harry Lyons and a colleague, Frank Cook, were met by an ashen-faced private secretary.

“He had a long face and muttered something about ‘Everybody’s gone mad today’.”

A press conference, held jointly by the Post Office and Buckinghamshire Police in Aylesbury that afternoon, attracted more coverage around the world than any other event in the history of the Investigation Branch. The banks affected reacted quickly and organised an unprecedented award of £250,000. The Postmaster General, Reginald Bevins, added a further £10,000 to that figure.

One of the IB’s first tasks was to investigate the rumours of an ‘inside job’ – fuelled by the fact that all three of the secure HVP coaches were simultaneously out of action for the first time, plus the gang’s apparent knowledge of the lack of security on the reserve HVP coach, the exact layout of the train, and the unusual amount of cash being carried on board that morning.

All 77 of the Post Office staff present on the train were background checked and interviewed at length by Lyons and his colleagues.

Investigators pulled together suspect lists within days of the Great Train Robbery and the first arrests were made within a week. By January 1964, enough evidence had been gathered to try 12 of the gang and 11 of them received heavy sentences of 20 to 30 years.

Three more suspects were arrested and jailed within five years of the crime, but two escaped from prison during that period, and the identities of a number of the gang have never been confirmed – including the rumoured Post Office insider.

Despite intense speculation and the enquiries led by the Investigation Branch ‘no evidence of collusion came to light’ and no proof of a Post Office insider has ever been found.

Does the Investigation Branch exist today?

The IB became the Post Office Investigation Department (POID) in 1967 and later changed its name again in 1996 to Post Office Security and Investigation Services (POSIS). Today, both Royal Mail Group and Post Office Ltd have operational Security and Investigation teams.

– The Postal Museum Team