The Atlantic RFK Jr.’s vaccine-safety investigator has previously used government vaccine data to publish research with glaring flaws. Mark and David Geier were a father-and-son team of researchers who operated on the fringes of the scientific establishment. They were known for promoting a controversial treatment for autism, and for publishing papers on the purported harms of vaccines that experts dismissed as junk science. In 2004, the CDC accused them of violating research protocols. In 2012, the state of Maryland sanctioned them. And in 2025, Health and Human Services Secretary Robert F. Kennedy Jr. tapped one of them to investigate alleged wrongdoing in a crucial CDC database.
For years, Kennedy has claimed that the database, which tracks adverse reactions to immunizations and is known as the Vaccine Safety Datalink, once contained vital information about vaccine safety—and that this information has been withheld from the public, scrubbed from the record, or otherwise manipulated. He wants David Geier to investigate it because he and his late father, a physician, studied it in the early 2000s, after they applied through a CDC program that allows researchers outside the government to access certain data sets.