The son of a well-to-do master upholsterer, he bought an estate at Cardington, Bedfordshire, and devoted himself to being a good landlord and to small-scale scientific interests, including breeding potatoes. His life changed when he was appointed High Sheriff of Bedfordshire in 1773. Normally an honorific post, it included attending the assizes, where he was shocked to learn that debtors who had paid their debts were sent back to prison if they could not also pay fees owed to the gaoler. He recommended that, instead, gaolers should be salaried; before agreeing, the justices responsible for the prison wanted to know what was done elsewhere.

Howard determined to find out. So began his travels the length and breadth of England, Scotland, and then throughout Europe, always single-mindedly visiting prisons rather than the 'sights'. He made meticulous notes, carried his own scales to weigh the prisoners' daily bread allowance, and noted whether the table of fees was displayed. In 1777 he published his findings as The state of the prisons, at his own expense, and distributed it widely. Later he became interested in the prevalent gaol fever and hence in lazarettos (quarantine hospitals). Believing that their dirty condition aggravated the death rate, he put his theory to the test by boarding a ship with a bill of ill-health, so that he was quarantined for 40 days in the lazaretto on arriving in Venice. By bribing an attendant he was able to whitewash the walls of his cell – and survived. However, when he later visited the appalling military hospitals in the Crimea, he became infected (though not, apparently, in the hospitals) and died.

The author is interested in sidelights on his life. Why was he so single-minded? A recent theory that he had Asperger's syndrome is quoted. Was he influenced by his mother's death when he was five? Or by being taken prisoner by pirates as a young man? Near the beginning of the book West cannot resist sharing the historical background she discovered during her research, with a number of 'probablys' and 'perhapses'. For example, 'perhaps he found himself passing close to the Bear at the Bridge Inn on November 18th 1750, where toasts were being made to a number of the capital's most famous citizens', with a 41-gun salute and a flourish of trumpets (p. 54). Well, yes, and perhaps he didn't, and it doesn't tell us anything about Howard; but it is an interesting historical footnote, providing a little background to the times in which he lived.

West is interested in his modus operandi – sometimes simply knocking on prison doors, sometimes having a letter of introduction from the British Ambassador. She raises a question ignored by other biographers: how did he overcome the language barrier? Surprisingly, for someone whose written English was far from fluent, he could pass for a Frenchman, and he knew Italian; elsewhere, once or twice there is mention of an interpreter. She does not gloss over his shortcomings. When he was presented with a chance to build two model prisons, the project failed because he could not agree with his colleagues. And there is the question of his son Jack, whose mother died a few days after he was born. There is some suggestion that John Howard was an over-strict father, and even before his prison journeys he often left him in boarding school (from the age of four and a half) or with servants, one of whom is thought to have introduced him to low life. After a troubled life he died at 34. Jack's father said he was always in his thoughts – but he went on travelling, and could not have achieved what he did if he had stayed at home as a dutiful single parent. Did he do the right thing?

The book ends with an assessment of his legacy. He certainly made people uncomfortably aware, and brought about some reforms, such as the appointment of prison inspectors; but the nineteenth century saw the grim silent and separate system, combined with useless toil at the crank or the treadwheel. But his name lives on and inspires those who also work for more effective, not to say humane, treatment of wrongdoers. As he said, '[t]here is a mode of managing some of the most desperate, with ease to yourself, and advantage to them. Many of them are shrewd and sensible: manage them with calmness, yet with steadiness: show them that you have humanity and that you aim to make them useful members of society' (quoted on p. 210).

There are numerous sub-headings, making the book easy to use for reference, but there are a few small oversights. Howard's mother Ann Pettit has no surname (p. xvii) and his collaborator and biographer Dr John Aikin no Christian name (p. 359). The family tree makes Howard the son of his father's second wife Anne Nesbitt (p. 44). Howard did not spend years in Ukraine (p. xiv). The index is good, but a few expected entries (such as his mother and step-mother) are not included. But these are small blemishes in an attractively produced book, in hardback – a new departure for Waterside Press. The book is a well researched update of previous biographies, and brings Howard to life as an outstanding – even if 'curious' - personality; few have done more to challenge human inhumanity.