Government Code 6254

Summary:

The Public Records Act does not require the disclosure of medical or similar files, when that disclosure would constitute an unwarranted invasion of personal privacy.

Other Relevant California Code Sections: 
Public Records Act, Government Code 6254.7 (specifying, inter alia that air pollution emissions data are public records) and 6254.13 (educational test data may be viewed by public officials)
Associated Federal Law(s): 
Uses and disclosures of protected health information: general rules : A covered entity may not use or disclose protected health information; exceptions.