The Animal Welfare Act of 1966 was passed to regulate the treatment of animals in research laboratories after it was discovered that many laboratories were paying thieves to steal pets for experimentation. Prior to 1966, animals of all kinds, including family pets, were being taken by thieves and given to laboratories for chemical testing. In response to public outcry over the situation, President Lyndon B. Johnson signed the Animal Welfare Act into law in 1966 to establish humane standards for the handling and treatment of animals in research.