There are few in the UK whose outrage at the extradition of British businessman Chris Tappin to the US has been sparked by a concern for his welfare. In itself, a jail sentence in the most developed nation in the world isn't the sort of cause that leads many people onto the streets with their placards.

But in fact, guilty or not, the conditions he faces in Otero County Prison, New Mexico, should worry anyone who believes in the principle of human rights. And this isn't a one-off case, but indicative of the situation that British prisoners - innocent or guilty - are facing in prisons across the world.

Some British people in foreign prisons have committed a crime, some are innocent, and many just spend years on remand without trial. But even for those who are guilty, whether it is gap year students buying drugs and not thinking about the consequences, expats who knowingly flout laws on displays of affection in public, or more serious illegal acts, surely their punishment should be loss of liberty and freedom, not a period lived in fear of violence and degradation?

Mention prisoners abroad to most people and, if they think about it at all it is likely they will alight on a memory of Bridget Jones, trapped for a few weeks in a crowded cell with 20 other friendly women. Less light heartedly - and more realistically - they might remember Warren Fellows, the heroin smuggler who suffered horrific human rights abuses and torture in Thailand's notorious Bang Kwang prison.

We are all familiar with images of dilapidated, rat and cockroach infested prisons, usually depicted somewhere out in South-East Asia or Eastern Europe. While we deal every day with clients who face those conditions, many are surprised to learn that out of the 1700 British people Prisoners Abroad care for every year, more are in need of help in the United States than anywhere else.

As one of the most developed countries in the world, it can be shocking to discover that the conditions people suffer in many American prisons are abusive, degrading and dangerous. According to Human Rights Watch, soaring prison populations, due to overly harsh sentencing laws, have combined with squeezed prison budgets to create a noxious environment for prisoners. Staff and resource levels are simply inadequate to ensure safe and humane confinement conditions.

As a result many American prisons fail to reach even basic standards of dignity, respect and safety. On a daily basis Prisoners Abroad deals with many Britons who face a struggle to survive in these dangerous and terrifying conditions. The impact can be devastating, both emotionally and psychologically and last long after the time they are released. Whether its flash backs and nightmares, terror of being with people and terror of being alone, or a complete loss of basic social and decision making skills, the sentence doesn't end when the prison doors open.

It is deeply concerning that the conditions many British prisoners face in US prisons violate the UN's Basic Principles for the Treatment of Prisoners. These call for all prisoners to be treated with humanity and the respect due to their inherent dignity and value as human beings. People should be free from cruel, inhuman or degrading treatment or punishment. Innocent or not, convicted or on remand, these should be fundamental rights for prisoners in any country.

But if these principles should apply to any country in particular, we could do no better than start with the United States. The country's own consitution demands it. The Eighth Amendment specifically prohibits punishment which is cruel or unusual, which includes the degradation of human dignity.

But the benefits of shining a spotlight onto conditions in the US stretch way beyond the country's borders. As with much else, where the US follows, others lead. Until the United States leads the way and ensures all its prisons are of a minimum standard which guarantees respect for all human beings, there can be little hope of meaningful reform to other countries around the world where prison conditions for those incarcerated abroad can be far worse.

Tappin may or may not be guilty, but regardless, the conditions he faces should be cause for concern for all of us.

Pauline Crowe is Chief Executive of Prisoners Abroad, the only UK charity caring for the welfare of British prisoners held in foreign prisons.

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