An animal welfare charity has been granted a court hearing to challenge the government over the legality in England of fast-growing broiler chickens. The UK’s first animal law firm, Advocates For Animals, has brought the case on behalf of the Humane League UK regarding so-called “Frankenchickens”, which can suffer from a wide range of health and welfare problems. The Humane League argues that the use of breeds that grow unnaturally large, unnaturally fast, breaches the welfare of farmed animals (England) regulations 2007, which state that animals can only be farmed if “they can be kept without any detrimental effect on their health or welfare”. Research has shown that fast-growing chickens, which reach their kill weight in just 35 days, can have higher levels of mortality, lameness and muscle disease than slower-growing breeds. Analysis by the Bureau of Investigative Journalism and the Guardian found that more than 39m broilers, chickens bred for meat, the vast majority of which are fast-growing breeds, were rejected because of diseases and defects at slaughterhouses in England and Wales over a three-year period – approximately 35,000 every day. The Department for Environment, Food and Rural Affairs (Defra) argues that it has no policy that condones or permits the use of fast-growing chickens. However, the Humane League says they are the industry standard, constituting about 90% of the more than 1bn meat chickens slaughtered each year in the UK. It was twice refused permission for a judicial review against Defra before Lord Justice Singh, at the court of appeal, said a full hearing would be in the public interest. Edie Bowles, solicitor at Advocates for Animals, said: “Not only is it clear that the law prohibits the farming of animals prone to suffering; combine this with a monitoring system which is inadequate to protect animals from extreme suffering, and we see a system which is as broken as it is unlawful. This broken system is also helping unlawful producers out-compete law-abiding producers by getting cheaper chickens on the market.” The case also argues that the trigger system, requiring vets at abattoirs to report problems, sets too high a threshold and that there is unequal treatment of chicken producers that comply with the law, incurring extra expense, compared with those who do not. Claire Williams, campaigns manager at the Humane League, said the court hearing was a milestone and that the charity “will strongly make the case that keeping these birds is wholly unlawful”. “These animals have suffering coded into their DNA, and we hope the justice system will rightly condemn that,” she said. A Defra spokesperson said: “We are proud to have some of the highest animal welfare standards in the world. All farm animals are protected by comprehensive and robust animal health and welfare legislation – including the Animal Welfare Act 2006 which makes it an offence to cause any captive animal unnecessary suffering.”