The US Supreme Court has declined to get involved in a capyright dogfight between Mexican fastfood chain Taco Bell and two Michigan men over a talking Chihuahua dog.

The two men, Joseph Shields and Thomas Rinks, claim that advertisisng executives at the California-based tacos giant stole their idea for a cartoon Chihuahua spokesdog (called "psycho Chihuahua") after they pitched it more than a year before the company began using the dog in commericals.

In 1997, Taco Bell aired commericals featuring a real Chihuahua who said in Spanish "Yo quiero Taco Bell" (I want Taco Bell). The company said it decided to use the dog after it was independently proposed by a larger advertising company.

The commerical, which has since been discontinued, was hugely popular - giving the company a huge market for spin-offs, such as soft toys and t-shirts.

Shields and Rinks sued Taco Bell in 1998, claiming that the company breached a verbal contract to use their dog. A federal judge dismissed the case in 1999 but Taco Bell, a subsidiary of restaurant giant Tricon Global Restaurants, appealed to the Supreme Court to throw out the copyright allegations after a federal appeals court reversed that decision in 2001 and reinstated the case.

The Supreme Court offered no comment when it declined the case.