Bill grew up in Baton Rouge, Louisiana, and attended Louisiana State University (LSU) for undergraduate and medical school. In 1990, Bill joined LSU Medical School teaching medical students and residents at Earl K. Long Hospital, a hospital for the uninsured.
During this time, he co-founded the Greater Baton Rouge Community Clinic, a clinic providing free dental and health care to the working uninsured. Bill also created a private-public partnership to vaccinate 36,000 greater Baton Rouge area children against Hepatitis B at no cost to the schools or parents. In the wake of Hurricane Katrina, Bill led a group of health care volunteers to convert an abandoned K-Mart building into an emergency health care facility, providing basic health care to hurricane evacuees.
In 2006, Bill was elected to the Louisiana State Senate. In 2008, he was elected to the United States House of Representatives to represent Louisiana’s Sixth Congressional District.
In the Senate
In 2014, he was elected to the U.S. Senate. He serves on the Finance Committee, the Health, Education, Labor, & Pensions Committee (HELP), the Energy and Natural Resources Committee, and the Veterans Affairs Committee.
Following his successful efforts to lower the cost of health care, secure coastal restoration projects to protect Louisiana families from natural disasters, reform our nation’s mental health system, and secure many other legislative accomplishments, Bill was reelected in 2020 to his second term in the U.S. Senate.
In 2023, he became Ranking Member of the Senate HELP Committee. He is the first physician to sit as HELP Ranking Member or Chairman since 1933, when it was called the Education and Labor Committee.
Bill is married to Dr. Laura Cassidy, and they have three children and one grandchild. Laura is a retired general surgeon specializing in breast cancer. She helped found a public charter school to teach children with dyslexia. The Cassidy family attends church at the Chapel on the Campus in Baton Rouge.