He was actually Lord Phillips of Worth Matravers, the Lord Chief Justice.

The false identity was part of his plan to experience at first hand the “payback project” — unpaid work that offenders do as an alternative to jail. Allegedly only three members of the Thames Valley Probation Service were in on the deception.

Lord Phillips’s day entailed cleaning up vandalism on The Lakes council estate in Bletchley, Buckinghamshire. “I was sweating away doing the weeding. After a tea break we brushed and washed down the inside of the underpass, attacking the black ceiling with buckets of water and squeegees. It was pretty foul work,” he told The Observer. “The passageway was fairly revolting. Someone had set fire to a wastepaper basket, so the ceiling was coated in soot and the dirt ran down my arms.”

He said that he and his cooffenders felt satisfied with their day’s work.

A recent report by the Chief Inspector of Probation said that criminals given community work orders were often going unpunished because there were too few staff to supervise them. Work orders included making costumes for the Notting Hill carnival “to help to break down racial and cultural stereotypes”.

Defending the scheme, Lord Phillips said: “I like to think that I am liberal, but that is not the same as being soft on crime. The idea that using alternatives to custody is being soft is wrong.”

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