Court-ordered access to high-cost drugs for rare genetic diseases, such as Fabry Disease (alpha-galactosidase-A deficiency), is a growing phenomenon as yet lacking systematic study. An observational, cross-sectional and retrospective study was conducted to characterize the lawsuits related to access to treatment for Fabry Disease by Enzyme Replacement Therapy in the State of Rio Grande do Sul prior to 2007. The study identified 13 lawsuits and 17 plaintiffs, 11 requesting alfa and 6 betagalsidase. The State of RS, the Federal Government, and 5 municipalities figured as defendants, in the form of joinder of parties or otherwise. There were 13 requests for interlocutory relief of which 12 were granted, and 2 sentences were handed down, both favorable. "Risk of death" was alleged by doctors in 4 prescriptions and by lawyers in the 13 lawsuits. The data suggest the lack of discussions combining aspects of medical efficacy and safety, cost-effectiveness, economic impact, and legal and constitutional arguments, which requires a specific policy for rare genetic diseases to standardize access to treatment.