Republican leaders of the House Science, Space, and Technology Committee sent a letter to Environmental Protection Agency Administrator Gina McCarthy on July 22 requesting that the agency release data behind health benefit claims used to support Clean Air Act regulations. In the letter, Committee Chairman Lamar Smith (R-TX) and Environmental Subcommittee Chairman Chris Stewart (R-UT) said that they would like to have the conclusions from this data independently verified and requested that the agency refrain from issuing any new rules based on the data until that time. The agency has said that they have released all available information, but it will request additional information from participating researchers.