In a Tennessee case concerning nursing care, the plaintiff relied on expert testimony from a neurosurgeon. The court dismissed the case, and the decision was upheld on appeal. See: https://www.nurse.com/blog/2019/10/23/wrong-expert-testifies-professional-negligence-case/
The judgment may be found here: http://www.tncourts.gov/sites/default/files/estate_of_herbert_ross_shelton_e2018-00862.pdf
