Oliver Letwin's binning of sensitive papers 'unlawful'

Mr Letwin said he was embarrassed by the episode

Cabinet Office minister Oliver Letwin breached the Data Protection Act when he dumped sensitive official documents in a park bin, a watchdog has said.

The Information Commissioner Christopher Graham warned that Mr Letwin faces formal enforcement action if it happens again.

The West Dorset MP has now signed a written commitment pledging to dispose of his files in a secure manner.

Mr Graham said: "It is clear that Mr Letwin has learned from this incident."

He added: "Constituents entrust their Member of Parliament with all sorts of personal information and should never expect the details of the concerns they've raised in confidence to end up in a park bin for anyone to see.

"It is clear that Mr Letwin has learned from this incident and we're pleased that he has co-operated fully.

"It is fortunate that most of the information he discarded was not of a particularly sensitive nature and was therefore unlikely to cause substantial distress to his constituents."

"Formal action"

A spokesman for Mr Letwin said: "Mr Letwin has signed an undertaking with the Information Commissioner's Office and will dispose of documents containing personal data in a secure manner.

"He has apologised to affected constituents."

But Mr Graham warned him not to dump any more sensitive documents.

"If we receive any further reports or complaints about Mr Letwin's conduct in this area then we will consider taking more formal action.

"I'm sure this case will also prompt other MPs to review their handling of personal data to ensure they're doing all they can to keep it secure."

Mr Letwin apologised last month after it emerged he had disposed of papers in a bin at St James's Park, near Downing Street, on five separate occasions.

He was photographed by the Daily Mirror, which claimed he had dumped more than 100 papers dating from July 2010 to September 2011, including documents containing constituents' private details and five Intelligence and Security Committee (ISC) letters.

"Personal assurance"

Labour MPs immediately called for an investigation into whether Mr Letwin's behaviour may have compromised national security.

But the Cabinet Office said Sir Gus O'Donnell, the head of the civil service, had spoken to Mr Letwin about the claims and he had been given a "personal assurance" that this was not the case.

"The cabinet secretary has looked into this and is content that no classified government documents were disposed of in this way," a spokeswoman for the department said.

Mr Letwin said he had been used to dealing with correspondence in St James's Park early in the morning before going to his office but maintained no sensitive documents had been involved. He has apologised to constituents who felt offended by his actions.

No 10 has said Mr Letwin's actions were "not sensible" and he would not be repeating them.