[1] O'Connor attended college at St. Bonaventure University on a US Army Reserve Officers' Training Corps (ROTC) scholarship, graduating with a major in biology and minor in theology.

[1] He is on faculty at George Washington University, where he served as the founding director of executive medicine.

[8] In January 2020, he was appointed medical director of St. Bonaventure University's Franciscan Health Care Professions program.

[10] A few days after his inauguration, President Joe Biden announced that he would appoint O'Connor as the White House physician.

[6] On July 7, 2024, James Comer, chair of the House Oversight Committee, sent a letter to O'Connor to ask him to come testify.