Caught on camera: Britain's best crime photography

What's more harmful – prejudice or war? Pollution or bullying? The finalists in a major new art contest tackle these difficult issues in arresting style

The photograph captures a fleeting moment of violence, but it tells the story of far-reaching abuse. In the dusty streets of Simlana, a small village in Uttar Pradesh, northern India, a man is attacking a 12-year-old boy.

The boy's name is Pardip and he suffers from a neurological disorder that developed when he drank contaminated water sourced from the polluted Hindon river. But whose is the greater crime – the man hitting Pardip, or those whose disregard for the environment first led to his condition?

The Centre for Crime and Justice Studies, an educational charity based at Kings College London, has just announced the winners of its photographic competition, sponsored by the Wates Foundation, which asked for visual answers to the question "What is Crime?" The resulting exhibition, to be mounted in association with The Independent, includes Pardip by Alex Masi. One eminent competition judge, the film director Ken Loach, named it as his favourite entry.

Rather than traditional images of criminality and justice, such as prison bars or policemen, the competition organisers asked for photographs that would "stimulate thinking about harm, injustice and crime". The exhibition contains a series of powerful images in three categories – Environment, Finance and Violence – all of which ask the viewer to recalibrate their sense of what is, or isn't, criminal. Open to anyone, the competition attracted participation from a range of amateur and professional photographers.

"The entries weren't necessarily judged on the excellence of the photograph," says organiser Anna Gilmour, "but on whether people had understood the ideas and themes and executed their response well. Of course, the professional photographers produced some particularly excellent examples, but we had fantastic entries from amateurs, too." The judges were also happy to find that they had attracted images from around the world.

The overall winner is Reyaz Limalia, who took his image, of Israel's wall across the West Bank, while on a trip to Bethlehem. "At first glance it looks like the graffiti on the wall is the crime," Limalia wrote. "But the true crime is the oppression of the wall itself ... The great tragedy is how the wall not only affects life for those there, but the impact it has on others around the world." Another photograph of the wall, taken by Jim Bulley, won in the Violence category, for its representation not of actual violence, but of "the continued violence against the Palestinian people".

Closer to home, the winner in the Finance category was Davy Jones, for May's Legs, his photograph of the damage wrought on his mother's body by years of working long hours for little pay. It recalls the brutally confessional family photography of former Turner Prize nominee Richard Billingham.

"My father died when I was 13, leaving my mother to bring my sister and I up by herself in Liverpool during the Thatcher years," Jones explains. "She worked two jobs; despite this we were on the breadline. Now 86 and crippled with arthritis this shot, for me, sums up the unrelenting work she has done for low wages and with little help." The finance category was inevitably dominated by images of the current recession. Four shades of blue in sixty-eight shut down shops, by Gregory Levitt, shows the effect of the crunch on Britain's high streets, where the shuttered stores starkly reflect the dire state of the nation's economy. "The rose-tinted notion of Britain as a 'nation of shopkeepers'," says Levitt, "is fading into the past."

Meanwhile, the Environment category included not just places, but faces too. Laura Pannack's Gemma was one of a series of sympathetic images of young people. Society, Pannack explains, "has a tendency to enforce blame on the younger generation for crime and violence. These negative stereotypes encourage further rebellion and prevent young people from gaining self confidence and aspiration; they fuel a lack of self-worth and anger.

"I have intentionally left it unclear whether my subjects are offenders on probation, pupils with special needs, private school attendants or other young people I have encountered. The forename of each young person gives the viewer a hint as to their identity without attaching stigma – and emphasises the fact that each of my subjects is unique."

Larry Gibson is not so anonymous. Photographed by Jo Syz at his home on Kayford Mountain in West Virginia, Gibson is the head man of the Stanleys, who have lived on the mountain since the 1700s, and are the only family there who have refused to sell their acres – 50 of them – to the MTR coal mining company. Gibson, the founder of a local environmental organisation that campaigns against MTR, travels the globe to raise awareness of the damage cause to the environment by the company's mining methods.

Some people chose to photograph the aftermath of violence rather than the action. The moving Jack Large, Chigwell 2008 by Phil Bedford shows the spot outside a closed police station on the Limes Farm Estate in Grange Hill, Essex, where, on 30 November, the 14-year-old Large was beaten and fatally stabbed after allegedly racially abusing another boy.

Alex Masi was named the winner of the Environment category, though not for Pardip, but for Dark Waters, his stunning image of the contaminated Krishni river's jet-black surface. "The river flows through the Indo-Gangetic plains of Uttar Pradesh, India," the photographer explains. "Where discharges from numerous industries enter watercourses and penetrate underground reservoirs, endangering the health of local communities and the environment."

Dark Waters suggests the crime preoccupying Masi was not – as one might first have assumed – the violence visited upon individual children by their elders, but the ecological destruction destined to impact not only on today's children, but on their children and grandchildren.

What is Crime? is at 198 Gallery, 198 Railton Road, Brixton, London, SE24 0JT, 9 July-28 August