SAN FRANCISCO, California - A US appeal court has struck down a 31-year-old Los Angeles law that made living in a car illegal.The ruling states that the "vaguely written statute" discriminated against the homeless and poor.A lawyer for the four people who challenged the law, said the ruling might force other cities within the 9th US Circuit Court of Appeals' territory to amend statutes that outlaw sleeping in vehicles.‘PEOPLE WHO LOST EVERYTHING’Carol Sobel, the lawyer representing the three men and one woman who sued to overturn the law in 2011, said Los Angeles' ban on living in cars was exceptionally broad.Sobel said: "People living in their vehicles are one of the great unidentified homeless groups in this country - formerly middle-class people who lost everything during the recession and are trying to maintain the appearance of stability so they can go to work." One of her clients was cited while waiting outside a church that served meals, another while on her way to sell her work at a local art fair.The ruling involved a 1983 law that prohibits the use of a vehicle "as living quarters either overnight, day-by-day, or otherwise".The court said the law was unconstitutional because its ambiguous wording did not not make clear what conduct would constitute a violation and "criminalises innocent behaviour".The decision came in a case brought on behalf of four people who were cited and arrested by Los Angeles police who concluded the numerous belongings in their recreation vehicles and cars meant they were violating the law.POLICE HOMELESS TASK FORCEJudge Harry Pregerson wrote: "Is it impermissible to eat food in a vehicle? Is it illegal to keep a sleeping bag? Canned food? Books? What about speaking on a cellphone? Or staying in the car to get out of the rain?"These are all actions the plaintiffs were taking when arrested for violation of the ordinance, all of which are otherwise perfectly legal."The officers were part of a police homeless task force charged with enforcing the ordinance in response to community complaints about people living in their cars.NEW ORDINANCE IN THE WORKSLos Angeles city attorney Mike Feuer, whose office defended the law before the 9th Circuit, said the city would not appeal. Instead, Feuer said, he would work with other officials to write a replacement ordinance "that respects both the rights and needs of homeless individuals and protects the quality of life in our neighbourhoods".The panel's ruling overturned a lower-court judge who had sided with the city and dismissed the case without a trial.