[5] Walker-Smith is the senior co-author of a fraudulent paper (along with Andrew Wakefield, the lead author) which claimed a unique gastrointestinal condition in autistic children that may be connected to the MMR vaccine.

This study is generally regarded as sparking the MMR vaccine controversy.

[6] In 2010, Walker-Smith was found guilty by the General Medical Council of professional misconduct who recommended erasure subject to appeal.

[4][7] On appeal, the case heard by Mr. Justice Mitting in the High Court stated that the GMC determinations were superficial and inadequate and so were quashed.

[8] In a statement reported in the book on the fraud by Brian Deer, Walker-Smith said: My case was related to entirely different issues to those that concerned Dr. Wakefield... Every investigative procedure I ordered was to find out what was wrong with the children.