By Olenka Frenkiel

It was a Wednesday night in Chicago's South Side, and 17-year-old high school student Eric Ersery was chatting with a friend on her front porch, when a young man walked up and shot them both. Eric died trying to protect his friend.

Eric Ersery was a model student and sportsman

He was an exemplary student, not a drug user, not a gang-member - just one of the daily victims of gun violence on the city streets. Yet Chicago is a city where handguns are - almost without exception - illegal. Illegal but still widely available. Last year there were 702 people murdered there, making Chicago the murder capital of the USA. Police say they confiscate 75 illegally held guns every day.

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James and Lamarr - casualties of the "gang-bangers" James and Lamarr, both in their twenties, don't figure in those murder statistics because although they too were shot, they survived.

Olenka meets James and Lamarr, trying to make lives after being paralysed by gunshot wounds

Both are now paralysed from the waist down, each injured in the regular shoot-outs between "gang-bangers" - the word for Chicago's gun-toting, drug-dealing street killers. Chicago is a highly segregated city, with a white population living mainly in the suburbs and the Hispanic and African-American communities mainly concentrated within inner-city neighbourhoods where it's hard to escape the violent culture.

Both James and Lamarr were gang-members, though now their days are often spent visiting local schools in an effort to persuade teenagers to focus on sports or music and not to get involved in drugs and guns. In a programme run by the Schwab Rehabilitation Hospital called In My Shoes, they talk about their injuries, their past in the gangs, and offer advice to their audiences on how to avoid the crushing peer pressure they gave in to.

James, who was a keen athlete when he was at school, has resumed his sports career and is now in the US marathon racing team competing in his wheelchair. He's hoping to show youngsters from deprived homes that with enough determination, any difficulty can be overcome.

But they both know they're up against a powerful sub-culture with vast sums of money at stake. "Getting a gun in this city," says James, "is like buying a loaf of bread... No," he corrects himself "a gun is like a dollar bill, it passes from owner to owner, a kind of currency. I could get you one this afternoon."

If it Worked for Tobacco, Why Not Guns?

The City Mayor, Richard Daley, who has watched Chicago's "gang-bangers" wreak havoc in the neighbourhoods has decided to fight back.

Olenka Frenkiel with Mayor Richard Daley: can lawsuits stem the violence?

With an eye to the success of recent cases against the tobacco manufacturers, the City has taken out a lawsuit against the gun sellers and the gun manufacturers demanding $433 million to compensate the city for "creating a public nuisance on the city streets". The money will help pay for the damage caused by guns. It will compensate the bereaved and help pay the medical costs of the survivors, those thousands of Chicagoans, like James and Lamarr, injured without medical insurance and dependent for their care on the taxpayer and the city's health budget.

Detective Jeannie Brandmayer (left) posed as a gang member out to commit crime - and still managed to buy guns

With the help of the City of Chicago Police Department, the Mayor has targeted gun shops outside the city, where selling guns for sport or self-protection is perfectly legal. Under-cover detectives posing as "gang-bangers" had no problem buying guns there, even though they let it be known the guns would be passed on and used as murder weapons back in the city. They gathered video evidence showing gun-shops helping them falsify the legal paperwork and turning a blind eye to the illegal use of the guns. Now the city plans to sue eleven Illinois gun shops outside the city limits. Another has already agreed to give evidence on the City's side in return for immunity from prosecution.

The Mayor is determined. "If the tobacco industry can be made to pay, if car manufacturers can be regulated, why not guns?" he told me. "This is the only industry that's never been scutinised or held to account - but that's going to change."

God Bless America

This is a land of contradictions, of the Second Amendment where a citizen's right to bear arms is enshrined in the Constitution. It's a country now reeling from yet another school massacre where a child takes a parent's gun and commits the kind of atrocity we normally associate with war-crimes. And it's a country where Charlton Heston, a Hollywood icon and spokesman for the gun lobby, can respond by suggesting: "Arm the teachers and ban trench coats".

At GATGuns, an Illinois gunshop outside the City limits - not one of those cited in the Mayor's lawsuit - Greg Trapino, the owner, admitted to me that when people are killed with guns which he's sold legally, but which have found their way into a murderer's hands, he cannot help but feel bad.

But he insists it's wrong to attack the industry. Whether it's civil lawsuits of the kind filed by Mayor Daley, or promises of more gun control legislation announced this week by President Clinton, he argues that restricting the rights of law-abiding people to own a gun is unfair and won't dent the murder statistics. "After all," he says, "I think about the two million lives saved every year by the use of guns in self-protection."

Greg Trapino of the Gat Guns shop, Illinois, demonstrates his wares

He handed me a gun: "very popular with ladies, this model" he said, and urged me to admire its handy lightness, its feminine style. When he saw me unmoved he tried a different approach. "All beautiful women need a gun. You've got a stalker. He's everywhere. Waiting outside when you leave the house, when you return, when you go to work when you go out to restaurant. You're alone in your house, just you and the kids, it's late - you know he's out there. You hear him at the door, He's banging and now he's trying to break the door down and get in. That's when a woman needs a gun"

I thought back to my most dangerous moments - from burglars to war-zones to drug-crazed gunmen in the favelas of Rio - and I realised that never once had it occurred to me, no matter how great the danger, that a gun might have been useful. I thought of poor Jill Dando, the British television presenter murdered on the doorstep of her London home this week. Would a gun really have helped her? I have my doubts.

Some areas of Chicago are certainly living in daily fear of gun and gang violence. When we took a short car ride around one neighbourhood with Kenny Ruiz, a street intervention worker with the YMCA, I was startled by how many signs of gang activity there were all around us. Kenny helps gang members who want to change their lives, but he's also trusted by local gang leaders, and knows all the ins and outs of the landscape - the clothing codes, the graffiti, the internal power struggles. Here, it seemed, the gangs were an inescapable presence.

When I visited Lisa Jones, the mother of Eric Ersery, the 17-year-old killed while I was in Chicago, she said "I feel like I've been running a marathon. I brought him up carefully protecting him, guarding him, steering him all those years and I almost made it. But at the last minute, someone took the finishing line away." But even at this moment of grief and mourning, Eric's godfather complained that the gun laws in Chicago were too strict and prohibited him, a law-abiding citizen, from having a handgun in his house to protect his family.

Britain and the US have much in common. But when it comes to guns, America is still a very different animal.